While I generally am very pedantic about bad grammar and misuse/abuse of the English languge, there are some manifestations which need to be let slide. I think this is one of them.
When you say, "Thank you," and the person you are thanking says, "No problem," what they are in fact saying is, "I was not at all inconvenienced by helping you, it did not cause me any problems to do so."
It's part of the self-deprecating nature of our interactions. We're not good at taking compliments, we're not good at accepting praise. We are taught humility to a fault; and this is another manifestation of that socially-induced humility. "No problem" is just another way of saying, "Glad to be of service."
At no point is there any intended implication that YOU are the problem (although by your repeated insistence, I suspect they may be changing their opinion on this score).
I mentioned a conversation with my friend at the beach the other day, when we were overhearing a very "yobbo" conversation (yobbo is the Aussie version of redneck, only distinctly Australian). As we quietly criticised the really bad grammer we were overhearing, we did remark that we must be awful intellectual snobs. But later thinking about it at home, I realised - what I so despise, is not ignorance. It's assumed ignorance, where people deliberately turn their backs on any outward signs of intelligence and education, in order to fit in with a social set of others doing the same thing. You then get a group of people chatting, all desperately dropping their Gs and flattening their vowels, in some desperate determination to be acceptable to the blue-singletted working man who, frankly, probably doesn't give a hoot.
If I'm talking to someone who is genuinely uneducated, someone who for various reasons never got past elementary school, I have no problem. It's those who HAVE had the benefit of a good education and who then pretend they haven't, who really make me angry. Their men don't have protte trouble, it's "prostrate" trouble. They don't damage their cruciate ligaments, it's their "crucial" ligaments. Their gardens have "fo-lij" instead of "fol-i-age". And at the most recent game, their football team was "frashed". Probably in the last "free" matches ("free" as in 2 + 1). Deliberate, obvious, assumed ignorance, for it's own sake - reverse snobbery. It's annoying and dangerous.
When husband & I first married, we spent a year living in a neighbourhood populated by such denizens. The neighbour on one side was a garbage truck driver (which is perfectly OK) who was condescending to us because we had been to university. The neighbour on te other side thought we were commies because we drove a Japanese-made car. He also beat his wife and kids, which didn't endear him to us, either.
And our wonderful artists' enclave of a village is not immune, either (as evidenced by our eavesdropping - they were people I know well, fellow parents at the local school, I KNOW how well educated they really are). I think the classic example is a former neighbour of ours from this village, a man who played tennis on a weekly basis with some of Australia's most celebrated (and genuinely modest) artists. The neighbour was a graphic artist, he made his living designing ads and posters for companies. Again, that's fine. But he chose to move away from the town because he felt isolated, he confided to us. There simply were no other people of his artistic calibre that he felt he could relate to, nobody he felt was his intellectual equal as an artist. When he said that to me, I was gobsmacked.
But then again - maybe he was right. There is no way he could ever hope to match the calibre of some of our local artists. However, I doubt he had the self-awareness to recognise this, and I know none of the local artists (the really good ones) would ever have made this man feel inferior. It's just not their style. This guys' conviction of his own superiority was breathtaking. I'm actually planning on using a thinly disguised characgter sketch in an upcoming short story. I sometimes do this, purely as catharsis. Don't worry, he will never recognise himself; he would never stoop to read any such 'trash' as I might write.
Most of the time when I hear bad grammar, or people murdering the language, I just grit my teeth. But sometimes, when I hear it from people who should know better (or who profess to know better) then I correct them.
The classic example I remember, was at a local writing group. One bloke would always take over the proceedings, because HIS work was clearly so important that it had to take precendence over any other person who had booked their work in to be workshopped. (I'm not kidding - he actually said this to us. "But MY work is important, it's going to be of great importance as a sociological text, at tertiary level.")
Then he read out his masterpiece, which was frankly nothing more than free association coupled with a jumbled collection of his adolescent memories, frankly of little relevance and even less interest to anyone. We stuck it out, perhaps even partly convinced by his self-proclaimed assessment that there was something incredibly deep and masterful in this, until we read, in several different places, where he had written "I should OF done this" (instead of "I should HAVE..."). When I tentatively suggested that the work was in need of some basic editing before he tried to submit it, he was scathing. "Well, obviously YOU might think that. Clearly this work is too exalted academically for you to comprehend."
I had been about to ask another question, but decided against it. Perhaps he might have reacted even more unpleasantly, when I asked him if there really was any literary merit in sharing with us all the intimate details of his first sexual experience - especially since he had been alone at the time.
I kept my mouth shut - he probably would have hit me.
Keeping my mouth shut - no problem.
Marg
Yesterday I had a chat with a young man via a telephone. We were discussing my Time Warner Cable account and lack of services despite my payment IN ADVANCE. (hrumph). 
Or is this a shared irritation? 
