Don't feed too many treats!!!
Chinchillas are just like children -- they would eat candy all day if you let them. It's up to you to make sure that they get the best possible hay, feed and clean water. Truly, that is all they need.
Treats are for us humans. I like to buy generic bite sized shredded wheats, break them in half, and then break those into halves, and you have 4 reasonable sized treats. Toys and sticks count as treats, too. Remember, anything that YOU hand your baby is a "treat" to them, whether it's an edible or a chewable.
Most things sold in pet stores are not safe for chinchillas, even though there may be a picture of a chinchilla on the package. Go to the chin supplies thread on this forum and check the sticky with the grand master list of chinnie items and who makes what. The Moderators are pretty good at weeding out non-reliable people, so you should feel comfortable ordering from people on that list.
When in doubt, ASK!!! The only stupid question is the one you don't ask!!!
Welcome to the wonderful world of chin ownership!!!