I used to work with people who did this. A lot of it does appear to be uniquely American, but the human element is this: these groups have all 110% convinced themselves they're saving those poor unfortunate people. A little marketing, they make some money, poor unfortunates get the help they need.

One organization literally refers to patients as "rescues". and this is one of the better actors in the space.

OTOH, these efforts help "raise awareness" and "save lives", more lives than if nothing had been done. It's extremely cost inefficient, but a self-interested naive outlook allows a straightforward rationalization process.