We have given out glow sticks and bracelets to kids during the fireworks without any problem, we usually just keep it low key, approach the parents and ask if it's OK to give them to their kids, or hand them to the parents themselves. When they see that we're with our own kids who also have the same thing, they are usually very happy to take them, especially because it ends the begging for the overpriced glow toys on sale.
The other way that tends to work is to have your kids hand them out, if they are old enough. Parents tend to be less suspicious of children and women giving away stuff, or at least of families doing it together. A single man handing out gifts can look odd (sad commentary on our society, isn't it?) but a couple with kids of their own just enjoying themselves and giving things to other kids around them because they have extra shouldn't raise any red flags with anyone.
Come to think of it, we did have one time when a father rather brusquely said NO and dragged his kid away while glaring at us like we were trying to sell something, but I think that was just a mis-understanding.
On the other hand we were in line HM one time and the little boy behind me was kind of whimpering because he was scared of the dark, so I pulled out a glow stick and gave it to his father for him, and he was so delighted he completely forgot to be scared of the ride. The parents were so grateful!
If anyone says no thank you, just smile and move on, no big deal.