That’s because someone has to do the work of providing the basic necessities, and if no one wants to do it, the ones who are forced to do it live in a dystopia.
In a true post scarcity, that shouldn’t be an issue.
If something needs fixing, then there is always somewhere where it needs fixing. I only value a plumber when my pipes are acting up, but that doesn’t mean that the plumber isn’t valued every day by someone.
If it is something that only needs to be fixed for the entire civilization once in a while, then that becomes an intellectual exercise for many to be involved in, and then go on to find and fix other problems.
Then you get rid of the pushing and the shoving. A large amount of “reprehensible” behavior is rooted and justified in the existential concern of meeting one’s basic needs. If you are not 100% secure in your ability to maintain your cushy standard of living, then many things are seen as a potential threat. If your lifestyle is in fact guaranteed, then there are less reasons to be concerned about someone else getting something too.