Why the hell would he blame himself for users making asinine demands? Are the users not adults? Are the users not fully capable of taking responsibility for their actions?
He can blame himself for worrying about it and wasting time on a huge writeup. Instead, he should offer to help for reasonable pay, have stock responses for rejections to prevent wasted time, and otherwise dont worry about the fact that companies are mostly selfish. That's life.
Just enjoy building and letting people use your app. Fuck the rest.
He should not complain about users with asinine demands. Let them make those demands. Either ignore them, or explain the situation and ask for a reasonable fee.