Some of this has already been said, but here's my two cents:
I have no problem with Ticketmaster trying to make a buck and providing a service, esp. over the Internet, which is helpful. And i understand that there are costs of doing business, and % on credit card transactions and all that.
But the main problems i have are the enomorous inconsistencies on the "convenience fees". There's no consistency on the level of the fees from event to even. Plus, they go up exponentially when the base price of the ticket is more. TM does it b/c they can get it away with it. Period. They figure if someone is already paying $100, they may as well charge them $15-20 more on the fees. Even when there are different ticket prices at the same show (i.e., $35 for a nosebleed vs. $200 for a floor seat), the fees will be much higher for the higher priced seats.
Plus, the fees at one show by one band will differ from another show with another band even when the ticket prices are the same. That has nothing to do with credit card fees, etc. The same thing happens with sporting events.
The other problem is that you never know what the fees are until the order is being processed. They don't list it anywhere until you're actually buying them. And I think the reason for that is that they set the fees for each individual event depending on what they think they can charge.
As long as TM has the market cornered, it will continue.