I'm going to yell at my friend for being nosy about a dinner bill
Why are you going to yell at a friend over a dinner bill?
Because he's now acting like my mom.
Friends can feel comfortable crossing boundaries, but if you don't want a friend to talk to you about your finances then you should tell them so. If you don't they'll continue to pester you about finances which will likely cause tension within your friendship.
This is something that I can't tolerate.  Since I'm not telling him about my private life, it is none of their business.
A friendship should be based on mutual respect.  You are within your right to tell them what you are comfortable with.