Exactly. Just because some don't use it does not mean it is extremely useful. Using Sunny F16 and 400 iso film, if your top shutter speed is only 1/1000 sec, the largest aperture you can use in bright sun is f/11.
I like to have more creative control than that.
Of course there are going to be those chiming in saying one should use a slow film in bright light, but the reality of the situation is that light conditions can be changeable, venues can change, time of day changes and more often than not the roll of film that was put in the camera has to be able to cope with these changes.
Using ND filters on an SLR is not as handy as on an RF, as the image obviously gets much darker.