I shoot weddings, so speed is important at key moments, but perhaps this is an exception.
Even wedding can better use anticipation rather than spray shooting. [Of course the concept of shotgunning a weeding is not a new one in the South.] When I anticipate an opportunity to photograph a wedding, I run the other way.
Sports. I bought an autowinder for my Contax RTS and it was a huge help if for no other reason than I didn't jostle the camera when advancing. It was too slow for much else but once in a while it came in handy. Then I bought a Canon 7ne for shooting hockey games which was dramatically faster. Lastly, a few years back my neighbor gave me his Nikon F-100 and it's amazing. The frame advance is great. So handy for all sports. (Also handy that it takes all those old AIx lenes.)
Of course having said all that, the two best action shots I have were taken with an old Yashica FX-2. :)
I've never needed the speed.
However I do appreciate a motordrive that moves along at 5fps much better than one that does only 1.5fps, even when shooting one frame at a time. The drives are noisy; the slower drives really drag out that noise. I hate that. I'd rather be shooting an FTb. For build-in drives I really do appreciate the near silent EOS RT.