And it becomes "typically American" when you see American tourists acting obnoxious.  The idea of the "obnoxious American" is so ingrained in your city that people actually refused to accept that I was American! (also because I apparently did not "look like an American," which is a little odd, seeing as almost every ethnicity under the sun is represented in this country).  It was flattering in a way, but illustrated a certain narrowmindedness on the part of the Parisians as well.  Which is, interestingly, the rap that Americans usually get.

Those who can make you believe absurdities can make you commit atrocities. -Voltaire

Oh, and you suggest that even Parisians are treated "rudely" at brasseries, unless they are regulars.  But I wasn't a regular and I really wasn't treated rudely.  (They were probably grummbling about me behind my back or something...)  

What's your theory?  Mine?  It also helps if you are a charming, attractive foreign young woman attempting to use what few French speaking skills she has ...

See, I really am an obnoxious American!

Those who can make you believe absurdities can make you commit atrocities. -Voltaire