Presumably most of these people are normal members of society with, ya know, shit the feds can just take. So I presume most people lawyer up, plead down to guilty with ton of fines and the feds go on their merry way happy to have enforced the law in a way that's cashflow positive (i.e. basically the same situation as tax prosecution).

Or, ya know, maybe having to divert planes because of drunk and disorderly passengers is a giant waste of time and resources. That costliness is why it is heavily punished. It isn’t the same as a drunk stumbling in a gutter and passing out.

The fact these people act out on a plane causes me to evaluate them as non-normal. We’re all on this human cattle car together. Shut up and stay quiet for four hours. The videos I have seen (likely not representative) the passengers were given several opportunities to behave before the extreme measures were taken.