I'm amazed at the attitude of the OP, calling people who use all of the bandwith that they pay for "freeloaders".
When he buys gas, does he put a gallon or 2 back in the stations tanks?
As far as caps go. 100 gig is not that much for a house full of teenagers. But at least (I think) they state the actual cap to their cutomers instead of having unstated limits and severe penalties for exceeding them - like Comcast.