I have to say on my rare trips to the US the immigration officials and even the secondary screening staff have been very friendly. Now the TSA staff are another matter, they really are a disgrace.

The rudest I have come accross have been in Australia. I have only been there twice but both times the immigration officer has been very rude.

Going back to the OPs comments about how much detail they require on your business the most ridiculous one for this was when leaving TLV. the security officials asked me wwhat I had been doing in Israel and I answered I had been doing training. So they made me do some of the training course to them in the middle of the terminal.