There is Japanese phenomenon called hikikomori. It's at least partly cultural, but one feature is the adolescent/young adult, generally male, excludes himself from society and stays in his room. Bottles of pee are part of the strategy, mostly as ways to avoid leaving the bedroom for ANY reason.
it happens in Japan and actually continues in various cases, because of the stress the kids are under (and their response to that stress when they feel they can't cope) coupled with deep parental shame which lead to enabling.
Parents don't enable to begin with; that comes later. The secret is to find a way to stop the enabling. If this is a stepson, you are dealing with issues of natural parent vs step-parent responsibilities, and who is actually trying to do something. A step-parent is a lot more powerless in this situation, not really able to enforce anything. This sounds like a case of natural parent afraid to push the issue for fear of once more losing access to the son. But it's not good to allow this to continue. Computer games require electricity, and this can be shut off past certain hours. here need to be ground rules and they need to be enforced. Bottles of pee - if he wants to pee in a bottle, he has to eventually deal with it himself, not expect someone else to, and not expect to keep it.
Marg