Photo man: they're usually ok, with the occasional bad tempered person.. Search the forum a bit, there's been several threads on traveling with pipes.
Basically it all comes down to this: be prepared, take off shoes, belt, change out of your pockets, phone, wallet, all that stuff. It goes either in your carry-on or in a little tray. Don't put bottles of water or large bottles of shower gel and stuff in your carry-on either. Make sure you know the rules. There are no rules against taking on cigarettes or tobacco products, including pipes. So they usually don't object to those. The couple of times I was asked whether they could check the bag was because of tins of tobacco. Although I usually have a couple in my bag without issues. They just looked at them, asked what they were, saw there was more pipe tobacco and let me go with it. Once one guy asked if he could pop an unopened tin of 7 year old C&D Repose I had found on a back shelf at a local B&M. I patiently explained I'd rather not and explained the aging of tobacco. He became very interested and let me carry it on without opening it. It's still in my cellar ;-)
You make their life easier, they won't hassle you.