Please Explain this Evil

Can anybody please explain to me why Sprint PCS can offer the ability to add options to my cellular phone plan--and make it as simple as clicking a button on a web page--but cannot delete no-longer-wanted options? They say the computer won't let them and I need to switch to a new plan.

Under this new plan my basic monthly charge goes up $5/month, but the total goes down $5/month (because I now can drop the unwanted option), I get a ton more minutes and they said they'd waive the committment to a long-term agreement. In the end, I'm satisfied with that.

Still, this seems like a darn inept way to run a railroad.