I am training DD right now and have no problem using treats. In fact, I've got a whole box of goodies that DD can pick out of when she's gone pee on the potty. It's random stuff I picked up at the dollar store - stickers, chocolate, toys, books, tattoos. It's working so far and she doesn't really expect something every time. Sometimes I will offer the box, sometimes she will ask or sometimes neither of us says a word about it and she enjoys her praises, hugs and high fives. I guess it all depends on the kid and the approach with treats. They have so much to learn in the first few years so why not reward them for some things??