Once they have your check card number, you can't escape their death grip on your $10 a month. Our family decided to join the YMCA because we needed the childcare and more flexibility, and I had to change my credit card number to get them to stop debiting my account. We went through the proper procedures (going in with a letter and turning in the key fobs), but they "lost the paperwork" and wanted us to come back in again. They refused to issue a refund for the debits that they made after we'd attempted to cancel, and were generally nasty about the whole process.
Yuck.
Yuck.
Yuck.