If you like the charms then keep them. With this particular item don't worry if it's a bit young (which I'm not sure charms are). It's not like your wearing knee highs or something.
i think i'd take them off of this particular bag and use them on a very simple classic bag as a funky unexpected touch. but if you keep them on the green bag that is cute too. . .either way. . .
I read that danglies are out, so I think you should take them off. But my guess is that most people won't know they're "out" or not, so you can put them on when you feel like having some danglies!
thanks girls, i took them off today- I can pass them along to my older step daughter , she is almost 14- she may like them or if not i know her sister will, she is 7