I feel like my brother in law is spoiled, and my mother in law indulges him.
Tell me why you feel that way.
He learns his way out of every issue, she pays for all his needs, he has never done anything by himself.
That sounds like a tough situation to finally dispel. What do you think you can do to help your BIL and MIL stray away from this behavior?
I am just going to yell at him and tell him to get off his lazy ass.
Wow, that's a little harsh wouldn't you think? They might not realize what they are doing is wrong, so I think it's best to just kindly let them know over a cup of coffee.