On one hand, yes service charges are a ripoff because surely it costs LESS to sell tickets over the Internet than it does to have a paid staff person sitting in a booth all day collecting money and handing them out.
On the other hand, prices throughout the economy are set according to what the market will bear. People may bitch and moan, but they pay the fees, and that's the only thing that matters from an economic perspective. For that reason, service charges will always be with us.