based on my experience it is just mostly because of the experience that they might get from the locals. trust me I have found bad foreigners who do things like shit, but there were even more high-nosed, egocentric locals who think they deserved everything and treat us like "babu" with little respect.
But as a professional, we have to be able to hide those feeling and should have to treat them as usual without looking where they come from either local or foreigners.
Yeah, I heard the same thing, some of them a bit annoying and even demanded a lot. They also complain quite often from what I saw. And it impacted to people who aren't like that which is pretty sad tbh. It sometimes throw me off but now I am getting used to it 😁 my trick is also by reading other's review of the place. Though that's not always reliable but at least, I can expect what's gonna be there.