It's possible that they banned someone by pure incompetence. I've definitely had my fair share of companies provide terrible service by probably just following some automated system as they are told. However, it is also very unlikely that there is a grand conspiracy on their part to ban people to simply maximize profits.

They do provide a pretty lengthy legal contract and terms to developers, which are partially outlined in this article. I think they just realize that the ball is in their court, and if the company wants to sue them then that is when they present the evidence.

I agree that it would be helpful for people that legitimately don't know and may have made some minor mistake to get more information to correct it, and prefer businesses be transparent when implementing their policies, but from a purely legal perspective it makes sense why Google doesn't do this.