Unfortunately, here in the USA we apparently don’t share your freedoms. They, immigration and customs, can ask you anything and everything. They have also empowered the airlines to ask questions pre check in, which occurs every time I fly from the UK). When I’ve refused to answer these questions (why should I tell my occupation to an airline clerk) the sticker they put on the back of my passport has flagged me for the third degree later on. But it’s worth it. Interesting that Global Entry and other services that are supposed to give you automated inspection still don’t protect you from intrusiveness at certain locations.