I'm not saying that the fine should be some fixed percentage of the revenue, I'm saying that it absolutely must be high enough to ensure the expected profit of

I'm not saying that the fine should be some fixed percentage of the revenue, I'm saying that it absolutely must be high enough to ensure the expected profit of just eating the fines and carrying on is negative. A sufficiently small fraction of speeding is revenue-generating that it's likely not worth the trouble, but in that example, you should probably be fined $10,050 or something. Though speeding tickets are a bit different because they already also come with points and a path to revocation of license.