They do drive the economy, but inhabitants of popular destinations tend to be disproportionately affected by noise, littering, and congestion. Mitigating this in part with better infrastructure and legislature should of course be the responsibility of the relevant governing bodies, but that does not negate the fact that some entitled people take on the mentality of being the monarchs of the places they visit rather than respecting the location and their locals. In short, it should be a social responsibility to watch out for one another and clean up after oneself both at home but also when visiting someplace as—essentially—a guest. Sadly, some people tend to act very disrespectfully and, even if it is just a small percentage of tourists, it leaves a bitter taste in the mouths of inhabitants of popular destinations. This is of course in no way inheritent to any culture in particular; a single percent of black sheep in a very large amount of tourists still amounts to a sizable group of troublemakers, which—in turn—ruins the reputation of tourists as a whole.

Oops, my take turned out to be longer than intended. TLDR; don’t be a bumhole when visiting someone else’s home.