VannATLC said:
Nice hate on the Jews. >.>
I don't think his comment was actually meant in the spirit of hating Jews -- all Borat jokes aside.
What he means (I assume) is that Tieflings are likely to end up in the same kinds of jobs that Jews did for many of the same social reasons. You have a human subculture that is markedly different from the dominant culture which is rootless and without a home. They look different (as a matter of physiology instead of due to religious dress codes) and people cannot really marry out of the community easily (due to the curse instead of religious reasons; a much more stark problem for Tieflings than for Jews who could convert).
As a result, they cannot blend in fully a society and must take up the marginal and yet useful jobs that people "in good standing" would never take -- for example, practicing usury (i.e. banking) -- just to find a way to fit in. This is especially true if the community resents members of the marginalized group holding the "good" jobs. These jobs, while disliked, are essential to a community and provide a reason for a community to tolerate their presence (even while reviling them for the sort of work they do).
In other words, the same European social pressures that drove real world Jews into being bankers (for which they were reviled) would probably apply to Tieflings. Tieflings will always be marked as separate. They have no homeland of their own. They will need a way to ingratiate themselves with a larger, disdainful human populace much like Jews had to do in Christian Europe.
That the people in question in his campaign setting are demon-touched was probably not meant to actually be an insult to the Jews. It's more of a coincidence resulting from Tieflings being perpetually attached to human cultures and yet always outsiders. (I pointed out the potentially insulting connection more as a joke than anything else; I didn't mean to open up a flood of accusations of anti-Semitism towards the original poster.)
In other words, I don't think the poster was actually intending to say anything like Jews == demonspawn. I think he was just finding a natural fit for Tieflings in the marginal, unwanted jobs.