@Oswald ******
I agree that respect needs to be earned. What I do is, I always talk to them. I hate awkward silence. Also, immigration officers are supposed to ask questions, it's part of their job. I find airport immigration officers are the surliest bunch, but you do sometimes get a nice officer mixed in with the quiet ones. At land borders, officers are usually very nice but it does depend on the border. The more remote the border is, the friendlier the officials are. At border crossings which are neither very quiet nor very busy and regularly used by foreigners, you'll generally be treated well, with minimal questions asked.