The problem is the opposite of that -- it isn't that the fine on low income people is too high, it's that it's too low to be a deterrent unless you make it high enough that scaling it makes is unnecessarily harsh for middle class people.

> In the case of breaking the law for hire, you can make the employer jointly liable, as is already the case for most crimes.

At which point you might as well just disband all large enterprises immediately because you've set up a system where you multiply the base rate of misbehavior by both the number of employees and the company's total revenue, which are both just proxies for size and so the penalty isn't just proportional, it's N-squared.

You also can't avoid the problem unless you go all the way to the root of ownership or people will just outsource the activity to a shell company, but then you end up imposing a billion dollar fine for littering because the offender works for a company which is owned by a mutual fund.

Easy fix: Set the fine as "N times daily wage, but at least X".

At which point low and middle income people all pay the same fine or as close to it as makes no difference, rich people avoid it through arbitrage and you have a system with no significant effect (except maybe that the super rich still pay less than the upper middle class).