Why do nonprofit organizations keep using Ticketmaster?

Had two recent experiences with Ticket Master. My one question is why do venues keep using a company that causes such a bad taste in the mouths of their clients?

My first experience was buying tickets for the Bruce Springsteen concert at the Xcel Center (big arena—home of the MN Wild NHL team). Went for the cheep tickets. Bought four tickets:

• Total for tickets (plus facility charge) $268.00
• Ticket Mater Convenience Charge $ 38
• Ticket Master charge for e-ticket $ 1.75
• Ticket Master Order Processing Charge $ 3.86
• Taxes $ 2.79

That equals:

• Non ticket master cost: $270.79
• Ticket master fees: $ 43.61

Ticket master added over 16 percent to the cost of the tickets. (And why is it with charging extra for an e-ticket—something that saves processing costs compared to mailing or will call.)

My second experience would have been a total rip-off.
Two $12 tickets (member rate) to a Minnesota Public Radio event at the Fitzgerald (home of the Prairie Home Companion). Choice was Ticketmaster or driving to the box office in downtown St. Paul.

For tickets tat totaled $29.00 (with facility charge) the Ticket Mater charges totaled $13.00. This would have added almost 45%.

I ended up going to the box office the next day to get the tickets and ended up three rows further back than if I had bought the tickets online

There are other options for venues:
So with other ticket services available, (Pro Ticket, used by the Guthrie Theatre is one that comes to mind) why do venues continue to use Ticket Master? You would think that venues (especially nonprofit organizations that have members how contribute money) would want to keep their customers happy and to keep costs to customers as low as possible.