It's no longer acceptable to be snooty towards people in these positions, but we haven't dropped the stigma totally, and now the acceptable way to view + interact with them is to act (in the performative sense, because many of us don't actually know) with deference, assuming that their lives are truly miserable and their dignity is on the line every day they work such jobs. The expectation is that we must feel sorry for them and treat them better than other people because of it, or treat them with kid gloves.
When you adopt such a stance, the idea of someone willingly going and doing one of these terrible no good jobs does seem patronizing -- it's masochistic even, and so is viewed as suspect and "touristy". When someone does such a thing they are "disrespecting themselves" by people with this view. If anyone ever tries to provide and alternative view and tell us that most people's lives in these positions aren't so bad by going and experiencing it themselves, however partially, we heap scorn on them. "They don't know what it's really like, it's horrible what these people have to do." "They have millions of dollars in the bank so their experience can be dismissed." Etc.