I'll admit to having snobby attitudes about photography, but I try not to impose them on others. Or even let them show in public. But I also use "A" and "S" at least as often as I use "M" mode, so I can't be THAT snobby. Most often this snobbery manifests as mentally criticizing photos; e.g., "hmm, you really thought that portrait was ok lit from behind with no fill?" or "might have been better without all the motion blur," or "what the hell kind of framing is that?"
The other temptation I try to avoid is the, to use a Vonnegutism, the "granfalloon." I.e., in my case the temptation to simultaneously create a bond with another photography enthusiast as such, and show off my knowledge of equipment and/or technique. I recently resisted the temptation to comment on a friend's Facebook-posted image thusly: "Great image. Shot with EF-S 10-22mm, great lens. I can tell from the shape of the flare."