When I scan film, the file name I choose for each frame consists of the frame number and the exposure date code I assign to the particular roll of film.
For those times when I shoot more than one roll, the exposure date code has "A", "B", "C" etc. added to it
And then I (often) add that identifying information to prints or digital displays of the image.
So frame numbers are part of my organization system, which tries to integrate both darkroom and digital versions.
The alternative would be to add them manually to the rebate of the film using a technical pen - been there, done that, don't want to have to do it again.