While I agree prisons are overused, making it a purely economical matter means it's just another investment. Benefit if you get away with it vs risk of getting caught. You have to be pretty draconian to make no one take that risk.
Banning people from an activity is also hard. They can just take a position where they advise others who will make such decisions, or other loopholes.
Jail time may not be the answer, and we clearly do a bad job of making these acts a financial risk (not to mention preventing recurrence), so your suggestion is undoubtedly an improvement over current day, but I don't think we can stop there. (Not that I have better ideas yet)
Banning people from an activity is also hard. They can just take a position where they advise others who will make such decisions, or other loopholes.
Jail time may not be the answer, and we clearly do a bad job of making these acts a financial risk (not to mention preventing recurrence), so your suggestion is undoubtedly an improvement over current day, but I don't think we can stop there. (Not that I have better ideas yet)