Indeed, I would suspect that real hitmen usually aren’t full time hitmen as an occupation. In the case of the highend examples you mention, they’re probably ex special forces or spies for that country that usually don’t get asked to do that, but do some other jobs for their paymasters. And most “hitmen” are probably actually from extremely poor countries and live and work in gangs doing all the usual gang illegal stuff in addition to doing hits (for relatively low sums).

I think dark web hitmen are entirely scams, but I suppose if we can literally buy heroin or crystal meth online from the dark web, it’s not entirely naive to think aprori that hits could also be purchased. The reason they’re not is probably that it’s actuslly extremely difficult to regularly perform hits in the West, and probably not a great business model to scale on the dark web for the average Joe who wants to pay only a few grand for a hit.