Are they getting enough food normally? Mine are a lot more grabby and nibbly when they're hungry. And do they have a wheel? It's good exercise for them. I swear one of mine might like the wheel more than he likes me, hahaha. You could give them bits of fresh fruits and veggies as treats as well, those might be more filling.
Gliders will beg. If I'm eating junkfood mine will ask for some even though I never share it. If it smells good and I'm eating it, they want it.
Accustom them to getting treats at only a certain time or place, and they should eventually stop asking for them all the time.