Having a kid with- chronic stomach issues, I've washed just about everything, LOL. Probably some things that aren't supposed to be washed, but you gotta do what you gotta do.
I do wash the foam pillows, but sometimes have to do them twice, flipping them so both sides get washed (part of it will stick up out of the water). I've got an ancient Kenmore dryer that does get them dry in one session - I make sure to put other stuff in there because if I dry the pillow alone, it tends to get flattened against the sides of the dryer and then it takes longer. Ideally, laundromat monster machines would work best I think.
I did have a pillow that was my favorite. It was probably 15 years old and well used. I like squishy pillows with not much form and this one was just *perfect*. Its final washing, the seam broke and when I pulled it out of the washer, all I had was the cover. Whatever was inside not only came out, but it went down the drain. So probably not a bad idea to check the seams if it's a floppy pillow.