Oh I see, well thats a topic im also curious about, especially as someone not living in America. It's the United States, except when it comes to beliefs, morals, laws, and more. I would worry all the time about traveling to another state because their laws might be different. Basically what most people do when they are traveling to another country, check what you are supposed to and not supposed to do.
Seems weird to me, as you are basically visiting the same country. Guess that might be mostly an opinion from an outsider though.
As an outsider myself, I feel like staying at the hostel all the time is the only safe solution. And still it's not this safe. If my memory don't betray me, there's at least one city where you can't have sex in an hostel if you aren't a legally married couple. So, take two rooms, one for you, and one for your partner, just to be sure.
Because you forget this, the differences can also apply to cities/counties, not only to states. Most of these laws are forgot since decades, but still exist. Sometime, like for this one about the sex in an hostel room, you can almost feel what happened.
A century ago, some influential guy found that his future wife had an affair in a hostel room. But since they aren't married yet, it wasn't adultery and there was nothing illegal. So, it led to this particular law because he really wanted her to have some hard times.