This is a tricky one. In general, I think any illegal entry into our country should lead to fingerprinting and a permanent ban on reentry or just about any path to citizenship. Marriage to a US citizen is different though, and I’d have to see the details and give that particular situation some though.
Will encourage the marriage factory to come alive again....$1,000 in your pocket to marry illegal so they can become a US citizen.
Near Austin, TX they are/were doing this and the same guy had about 8 marriages and divorces.
IF you want an illegal spouse, follow the law or what was the law.
The basic idea behind the penalty was to stop sham marriages.
If someone comes here on a 6 month visa, falls in love, and marries an American, that is reasonably straight forward, and the non-American, in some cases, might not even have to leave the country to get the proper papers.
On the other hand, if someone comes here on a 6 month visa, gets arrested here 3 years later, and then suddenly marries an American, most likely that's completely bogus, and the penalty kicks in.