I don't understand why anyone would use a check to make purchases at a store. First of all, it's not that secure, as several people have access to your personal information. It takes time to write a check. Since they are using telecheck the funds are taken out of your account immediately, so there's no advantage there. Why just not use a credit or debit card?
I can't imagine why you would be charged $10 for using a debit card? Ever since BOA announced they were going to start charging fees, people started complaining and switching banks. So banks have decided to give up on that idea.
I'm guessing that Telecheck may charge a few for every check that they process. I would call telecheck and talk to a manager to see what can be done. I'm sure if you notify them you'll be writing checks, they can make a note on your account.