paintballs are non toxic. TO HUMANS. that doesnt mean feed them to your dog. there have been lots of cases of dogs having bad issues from eating paintballs including deaths.
truely most of the bad situations have been dogs eating a lot of them but why risk it. esp if you have a small dog. all animals react differently to different things.
the label of non toxic doesnt make it 100 % safe for everything. grapes will shut down your dogs kidneys. onions will make them anaemic etc. just because its safe for you doesnt mean it is your pets.