I generally find french "snootiness" to not really be hateful or judgemental so much as pride in their own culture... They think their foods and snacks and opinions are the best around, at least the french from france. But I dont find it obnoxious or anything. Its just a sense of "class" or "refinement" that is appreciated. In fact in my time in france I found an appreciation in the "snootiness" which often manifested as food and dishes with an attention to detail in its presentation, preperation, and sourcing of its ingredients. You get a feeling of fine dining at almost anywhere you go, and they take pride in that.
I almost never experienced that snootiness as "americans suck". I think americans might just take it too personally. Only time you might get knocked down a peg is if you try to argue an american equivalent of a food is superior... they will let you know you are wrong :)