Maybe a little different of a take.

1. I don't think I would want my dog (don't have one ) eating treats from another person's pocket. If the dog has a sensitive digestive system etc. it could mean trouble. So, I don't think it is unreasonable to ask the owner for his/her treats.

2. Why don't you email the outline to each person and let them print it out. You won't have to tangle with the awful copier.

3. If they can afford $110 for a dog training course, then the other items are not an issue either. Let them buy their own clicker. Just tell them up front. Or raise the price of the course, to include the clicker and good copies along with treats. If they will pay $110, will they $115? Probably.