I think the safest thing is to not buy these things. Buy the most serviceable and reliable vanilla physical products (a watch, not a Rolex). Don't buy music, and certainly don't have music or movies on your laptop when you cross borders.
Anything protected by commercial IP is becoming too dangerous to have around, legally obtained or not.
- What if it was a gift?
- What if he is not aware of the brand and thought it was just another bag?
Where would a person learn this? I've heard the brand name Gucci before, but I had no idea it was so expensive. Naturally, I'm not the sort of person who would buy such things because of the name of the company who made them, but it also wouldn't seem strange to me to see a given brand on sale outside of a luxury store.
I guess we each have our own set of assumptions about what the "average person" should consider common knowledge.