I'm pissed at Gold's gym

My contract with Gold's gym expired ALONG time ago but on a month to month basis with them. I pay for my bf and my membership. For this month, they charged me $15 dollars more per person. I went from paying $40/mo to $70/mo!!!! I had no notice. I called corporate to dispute the charges. They said it was plastered all over the gym. I told them it's been awhile since I went to the gym. And then he tried to call me out saying that he sees that I've gone there 5 times in December. I told him, if you plastered it the times that I was there I think I would have noticed. When I spoke to the ppl at the gym, they said I probably wasnt there when they had the signs. (Don't be accusing me of lying!)

And then, we kinda got into it. I told him I've been a member for YEARS and you just raise it by 15 bucks with no notice! He said that the company can really do that! And then he used the analogy about how Sprint would raise their rates too! Let me tell you...he shot his own self in the foot!!!! I told them NO THEY DO NOT! Even when my contract was up they left my rates ALONE. Even when they had new rates, they left mine alone and charged NEW customers more. And his response was, "well every business works differently." SHUT UP! You're the one that brought Sprint up, you dummy! He used another analogy about a clothing store, but it was so lame, it's not worth mentioning.

I told him this is so rude of Gold's gym. I've been a member for YEARS and you would change my rates without even mailing me a letter! I told him they were disrespecting me when I have paid on time every single month. The least they could do was to MAIL ME A LETTER PERSONALLY! You gonna jack up my rates to $15, you better cough up some stamp money to mail me a letter! I said I've been paying on time with no problems ever, and you treat me like I'm not even important enough to write a letter! And all he could say was, there was nothing he can do. And they wont even take those charges off or anything. I was pissed. They say that that was what I signed into when I joined gold's gym...that they can raise rates when they want to. But what does that mean to ME when my contract is up?

After I got off the phone with him, I went to my bank to dispute the charges. And tomorrow, I'm going to write a cancellation letter to Gold's gym, and stop further payments from them. I think this is so wrong of them. What stops them from charging me any crazy rate they want?

What do you guys think?
Sorry so long...I've been complaining alot this week.