Although I'd agree that $10 for that much bandwidth is unreasonable, what about the fact that many customers sign up for more bandwidth than they actually use, just for the sole desire to have it if they ever needed it?
For example, a host might have 100 customers on packages of 200 GB, but how many would actually be using that much?
MOD NOTE: Post edited for advertising content. Advertising in main forums is prohibited. Please consult the Rules for details: http://www.hostingdiscussion.com/rules.php