I was just in the parks, and took glow sticks. I got 200 8" sticks with connectors, including shipping off ebay for just under $20. TOTALLY worth it. We had a large group, with three under-10's, and having everyone where a glow bracelet, necklace, headband, etc made them very spottable in the dark. AND, it was big entertainment for the kids while waiting for the parade/ride/show were we doing once it got dark. None of the kids asked for any of the other glow things being sold - they were so thrilled with the sticks we had.
I DID carry some on the plane. I had about 25 wrapped in plastic wrap, then stiffened with a few layers of packing tape (and my Pampered Chef ceramic cutter thingie to get into them) and I was fully prepared to give them up if necessary. They were never mentioned. I think that will completely depend on the security you're going thru... I've found that small airports are MUCH, MUCH more picky about what goes thru the line.
The rest were in the cardboard tube they arrived in in my suitcase, checked.
I will absolutely bring them again. They were actually a little heavy to cart around, but we had a stroller.