If you blatantly ignore and NDA, and then make a lot of money from it, then the 'small startup' will have a ton of money because the prize is huge, i.e. a % cut to lawyers who can work pro-bono.

Imagine you have a $10B company and some bonehead PM steals info from some small startup, for some stupid small project - it puts everything at risk.

In most case, I think you have boneheaded actors, usually not acting in the best interest of the company.