To all in that “90%” who feel bittorrent users are stealing from you: This is simply a reality for shared bandwidth type services such as cable internet. I am not saying they are right to use up all the bandwidth, only that it’s a reality that there will always be at least one person using more than their fair share. If you want a guarantee of bandwidth then you should purchase an account with a dedicated bandwidth service provider such as DSL or wireless broadband.
To that “10%” who are purportedly using up all the bandwidth: If you have a shared type service then it is your responsibility to make sure you do not use more than you should. Most torrent applications have built in capping utilities to keep it from using up all of the available bandwidth. Ask your ISP what would be an acceptable sustained transfer rate at which you can cap your torrent application. If you don’t want to take the trouble to set your own limits then you should probably look at dropping your shared bandwidth service and picking up a dedicated service instead. It will likely cost a little more but the fact is you are already using more bandwidth than what you paid for.
To shared bandwidth service providers: Your service needs to very clearly state that it is shared bandwidth. Competitive environment is absolutely not justification for lying (flat out or by omission) in your advertising or contracts. You also need to have a very clear statistics system that divides the bandwidth by the number of users in that lump and tells a user what percentage of the bandwidth they are using in relation to the bandwidth that has been allocated to them.
To dedicated bandwidth service providers: If I purchase 10 megabits per second of unlimited dedicated bandwidth (meaning no limits other than the bandwidth cap) then that bandwidth is mine to use as I see fit. It is the ISP’s responsibility to make sure that it can supply the bandwidth it has sold to me. Period. You also have no say in how I choose to use my bandwidth. If I choose to leave a torrent running all day every day and pushing my connection right up against my account cap all month long then that is my choice. I am not using anyone else’s bandwidth so I can do whatever I want with it. If you are unable to supply the bandwidth you have advertised then you need to change your advertising to reflect a level you are capable of providing. Setting an unspecified monthly bandwidth limit is not acceptable for you under any circumstance.
There has been a rash of ISPs selling more bandwidth than they can actually supply and using tactics such as unspecified monthly limits to try and cover it up. These companies need to be avoided with the vigor normally reserved for roadkill.
If your ISP is throttling your usage then check into the type of service you have and take appropriate measures.