Here's the problem: low light stage cinematography, as in clubs back then was both technically difficult and expensive to do if one wanted a halfway professional look, which is why one normally only sees footage of bands from that era in A) well-lit television studio spots and B) well-funded outdoor festival movies or other commercial film productions.
Then there's preservation: not every format is still accessible to play nor non-degraded. For example, the heretofore unknown footage in the Raw Power dvd was taken by someone who worked in television news broadcast and hence had access to the specialty equipment required, even though it was silent with the assumption that canned music would be superimposed for the news piece (which was not to be.) This person gave a Betamax (the video format preferred then in news broadcast) copy to another friend, who gave another copy transferred to VHS (it was the 1980's) to a person who eventually digitized it. This last format change was funneled to the production company making the RP dvd, otherwise those would have been the three people in the universe with sole access to 50% of the known footage of the Raw Power Stooges.