However, gaijin is an insulting term, regardless of whether some Japanese hottie wants to use it to hit on you. The commonality of its use does not make it less of an insult, even if you decide to use it. Let me put it this way: you go to great lengths to point out the use of the terms "Japs" or "Nips" as insulting, but defend the use of gaijin as normal and non-insulting. "Jap" and "Nip" are just shortenings of normal words. "Gaijin" is profoundly more negative, on many levels. I pass the ball to you.
Just remember that they will eat you, if their supply lines are cut!