The benefit is that you still profit from actions that break the law.
If it's possible to stop breaking the law in a way that the revenue drop is smaller than $30M a year, they'll possibly do it at some point. However, it's possible that the drop would be bigger, in which case the $30M/y fine is just cost of doing business.
If you find a $100 bill on the street, do you pick it up, or do you just assume it can't be real because surely someone else would have picked it up already if it was real?
There's a staggering amount of inefficiencies in large corporations. Just because a corpo is doing something a certain way right now, doesn't mean it's necessarily the result of a higly optimized process or rational risk/benefit analysis.
If it's possible to stop breaking the law in a way that the revenue drop is smaller than $30M a year, they'll possibly do it at some point. However, it's possible that the drop would be bigger, in which case the $30M/y fine is just cost of doing business.