As long as your read the ingredients and the are similar to that from the glider site it should be fine. My vet says that if you eat a yogurt drop and it feel greasy in you mouth that you shouldn't feed that (however safe it may look).
You can buy many type of treats for gliders as long as you read the ingredients and they seem safe. One good recommendation is to never feed gliders foods that contain artificial ingredients.
Still there are people that would fee stuff like marshmallows, cheerios, and such. Mine, I've found that they don't like dried fruits or most nuts like pine and almonds; but they love sun flower seeds and pistachios. The only thing with nuts is that they are fatty and contain proteins, so you should not feed to much of these, and use them only as treats.
Hope this is helpful.