In my last car that had an aftermarket headunit with a remote, I always kept it in the door armrest and used it pretty often. It made for easy channel/track switching while shifting, with the remote in the shifter hand.
Saab has a stock/integrated stereo and I dont miss the remote though.
Back when I had a nice head unit and sound system I used that remote all the time, It was nice because I could keep my hand on the shifter and change songs without taking my hand off.
Of course thats just because I am lazy, now with no remote I could care less.