Tow Boat Contract Law Question

Quick question:
I was on my way to the Thousand Islands for a boating trip when my engine blew. Naturally I called a tow to pick me up. I was told it would be 200 USD per hour, and agreed. Going ~28 miles per hour we were ~45 minutes off from shore. The tow company with twin 150 horsepower engines (capable of 60mph) somehow took an hour and forty-five minutes to travel the same distance as I was able to in 45. On top of that after tying to my boat and starting to tow us in I realized he was only going 6 miles per hour. I understand you need to drive slower while towing a boat in but, driving boats my whole life, the prospect of 6mph towing is ludicrous. It's obvious to me that they do this for extortitory reasons. Had they told me that ahead of time I would have swam home. I informed him as to how ridiculous this was and he said it was a part of their contract and it was too late to go back on it. I then asked him for an estimate and he said it would be about $1400. So here's my question: as the strongest bargaining party in the contract are they not required to lay this out in plain terms? I see this analogous to an ambulance that charges by the mile going only 3mph and retroactively (after they showed up) telling you that it's part of the contract that you've already agreed to. Thanks for the help!

-Sue