Distracting Gesticulation

Some television programmes have a 'signer' gesticulating in one corner of the screen. I find that makes it hard for me to concentrate.

It is usually possible to select subtitles. I usually do because non-verbal noise in programs sometimes makes is hard to follow speech.

Subtitles are optional, one can switch them on or off according to taste, but the signer is not optional. One gets the signing whether one wants it or not, and however ugly the signer happens to be. Why can't deaf people use the subtitles? Why can't I turn off the signing?