Earlier quoted context omitted.
Unless the fines are 2-3 times the amount stolen. That would cut into the legitimate portion of their income and likely be a strong deterrent.
The problem is that you have to know how often they get caught in order to decide the amount. For example, if they only get caught 1/4 of the time, the fine needs to be greater than four times the amount stolen to make a difference (force the expected value of the behavior below zero). In practice, it would probably need to be quite a bit higher than that since people who do this sort of thing are likely risk-takers/…
The administrative penalties could simply be scaled to be much scarier without needing to go that far.
Personal financial liability (piercing the corporate veil) with limited negotiation of terms (and since personal credit is usually factored into business credit, that bankruptcy will greatly impact your ability to do business), administrative dissolution of business, very very large fines, and so on.