Extra security scrutiny transiting in IST?

My family and I just got back from a warm and enjoyable (other than being stuck at NRT for 3+ days) in SEA (PEN, HKG and SIN). We took TK back to NYC. When we were transiting at IST, we went through 6 layers of security screening from disembarking and getting back onto the connecting flight and was wondering if that was a normal practice. They said it was a random screening, but we definitely got the impression that anyone going to America was going to get extra screening and one of the guys alluded to the fact that my parents were "older" Chinese (US Citizens) folks so they had to make sure they weren't trying to sneak into the country. They asked for their printed itinerary for UA on the award flight to see that they actually came from the US. Obviously, my wife (SG Citizen) and folks were getting a bit annoyed and peeved at it all. I enjoyed the hard product and soft product for the most part, so I would consider using them again but the security screening was a bit much. Anyone else have similar experiences?

 

I've had a couple extra layers of security screening in IST for US-bound flights and in one case an EMPTY water bottle was confiscated for no apparent reason. But overall it wasn't so annoying as to put me off on the experience.

 

Empty? That's weird, but not unheard of. A co-worker of mine had an empty coffee mug confiscated.