humble minion
Legend
There's plenty of ways to attach PCs to society that's don't require skeevy things like the caste system or droit de seigneur (which is also at least quasi-apocryphal...) being implemented in game settings. Hell, at session zero, simply require that PCs detail all the members of their family (no orphans!) and where they actually live. If this doesn't work, a bit of enforcement of the encumbrance rules can often do the job. So, Mr Str 8 Rogue - you want to go to an audience with the local petty noble. Do you have any family members or guildfellows or old school chums here that can obtain an introduction for you? No? Well, you're just going to have to dress to impress then. Do you have a set of decent boots? Other than the ones you've been wearing while wading through the Deathsewers of Glop the Slimelord? How are you carrying them? In your bag of holding next to the collection of drippy monster bits that you're planning to sell to the alchemist in the next town, huh? I wonder what they smell like now. How are you keeping your court clothes clean? There's no ziplock plastic bags in Faerun, you know. Are you even CARRYING a hairbrush, or a razor, or soap? Go to a barber? He's not going to even let you in the door looking like that. Oh, BUY a new set of clothes? Well, again, you'll have to convince a reputable tailor to let you through his door, but first, how do you know who the respectable court tailors ARE in this city? And are you aware of the significance that wearing certain colours has with respect to local politics? No? Well, you're just going to have to take your chances and hope you don't wear violently revolutionary anti-aristocrat colors by mistake. Jeez, it's be nice if you actually knew someone trustworthy here you could ask...One of the more common criticism of D&D is that the PCs have very few attachments to society. i.e. The hobo part of being murder hoboes. But you're right, ignoring those institutions is certainly an option. It's the least interesting option in my opinion but it is an option.
Though of course quite often game settings are deliberately designed with weak, loose 'society' simply because that means there's more lawless bits, wilderness, bandits, abandoned settlements etc for PCs to interact with (and because paying taxes in-game is no fun!) But arguing that PCs need institutions like sati or nostril-slitting or enclosure-driven starvation in-game to actually bind them to a society is a bit of a false dichotomy. Hell, these are things that in fact might drive people to WANT to abandon society! There's piles of other social practises that can do the job of reducing the incentive to murderhobo without wallowing in the worst injustices of human history.