[Ayoka]

My trainer likens treats to a dog "working for pay"

In Bear's obedience class we use treats and a word marker "yes" (some people use clickerrs) to teach the dog what he/she is supposed to do and get things really ingrained into their minds. When they have it down with treats, then we start randomizing treats and expecting longer stays etc (but still use "yes") so that they learn to do the work with & without treats. I belive I read something somewhere that said that the randomising actually reinforces the behaviour rather than discourages it. I don't think I will EVER get rid of the treats completely, but I do expect to use fewer as time goes on.

Many competition rings don't allow food rewards so dogs in those environments work in the ring without reward but I'm sure that in any other situation/environment they do get rewards.

Also I think that some dogs will work for different levels of rewards...some are ok with praise and pets while others need something more like a toy or special treat. Bear is so food motivated that he will work for his kibble while other dogs in our class won't even respond to freeze dried liver!

If your method is working I'd say you don't need to change it but I don't think that means that there is anything wrong with using food rewards.