I would like to offer that I'm no fan of dealing with the big 3 (Comcast, Time Warner, Verizon) and routinely no bid their jobs. If you think they are shitty on the customer side, you should see them in construction environments. But I do know what it costs to run FttP and FttX and that figure starts with 7 0's behind it, trust me.
And no offense I'd rather you pay the extra 30 bucks a month for utilizing a large amount of bandwidth than have my bill increase every other 6 months.
Edit: And you already knew going in you were going to use more bandwidth than spec'd, that's not their fault, its yours for trying to be a cheap fuck.