My moms DTV account was initially set up for service in three rooms. That was a long time before HD. One room had a TiVo receiver and a $10/mo charge for that.
With the change to HD service (two rooms only) the TiVo was discarded. But the charge remained. For a long time it remained. I recently spotted this and called DTV on it. They removed the charge.
The total on the next bill was $.50 higher. The basic service went up about $5 and a regional sports fee went up about the same.