Contracts that "hide" things in them tend to get invalidated by the court if you refuse to pay. Courts take a dim view of attempts to trick consumers.

If you didn't read the contract before you signed it, though, next time you should.

When I bought a house, they gave me a stack of paper about half an inch high to read, including a document for me to sign that said "I have read and understand the documents." So I sat there with the agent and read every word of it. She was clearly quite irritated with me "wasting her time" by reading it, but too bad for her.

A couple issues I was particularly interested in was what happens if I default on the mortgage, and what happens if I prepay the loan.

BTW, I recommend reading the fitness club contracts first. They are negotiable, but if you don't read them you won't know what to negotiate, and will be paying the "sucker price".