wireless contract

I was a long time Rogers wireless customer as well as a cable TV and internet customer. My last bill was for $576.00 and I decided to look for another wireless carrier. May/2013 I went to another wireless company. The transfer was smooth. My Rogers bill had a zero balance. I was not under a 3 year contract, (I assumed) but a monthly contract and had been for years. My phone way paid for years ago. In June/2013 I received my Rogers bill. $113.00 for cable internet, which i had expected but Rogers added $300.00 because I had the MY5/MY10 plan on my cellphone. It was a plan promoted to save on long distance charges to family and friends. It never occurred to me that it was actually a underhanded way for Rogers to commit me to a "long-term contract".
I will not pay the $300.00 and I would advise any Rogers customer who has the MY5/MY10 to seriously consider the ramifications of such plan.
Thanks for the venting.. Daryl Keating.