For me - the cost of the class is probably manageable -
If I knew that it would be okay to bring supplies "from home" - instead of having to buy them from the LQS for that class - I would probably be more interested/willilng to sign up for classes.
I also don't want to deal with the snobs/elitests who have better/newer/more expensive things to use.
(Only exception to that - if people are learning how to use a particular machine - then it makes sense for them all to be using similar machines.)