We love our smartphones, tablets, apps and whatnot, but we have to admit, we've noticed technology has made the world a slightly ruder place. Stores now have signs at the checkout requesting shoppers not be on the phone while they check out. Certain restaurants have even banned cell phones, because what chef wants people paying more attention to Angry Birds than the dish they've served up? We got to thinking about other commonplace behaviors that once upon a time were considered to be rude, rude, rude.