Shadowrun predates the SERRAted Edge stuff by three years.
And it's mostly because elves are the pretty people - pretty attractive, pretty arrogant, pretty long-living, pretty much an asshole. When Mr. 'I'm going to live 300 years' screws you over for a power struggle that's been going on since before you were born, and he simply doesn't deign to inform you he's getting you tangled up in it, it's very easy to distrust him. It's the same reason why you never cut a deal with a dragon.
Understand, though, that this mostly applies to those who walk into the room with the attitude of 'I'm the greatest thing here since water was invented' - you know, your pornomancers. If I had a player who was going full-bore Pornomancer, I'm pretty sure I'd make every non-elf (and a few of the more 'normal' elves too) interaction start out as a hostile interview after the first two or three times, excluding a few of the 'ooo, elves are sooooo wonderful' fantasy-on-the-brain idiots. I know Suki would sit calmly through his smarm, stand up, and put two through his brainpan ... and certainly wouldn't approve of working with such a shit.
