Captain James is correct and the clips shown on Bandstand did not include audio. Back in the day there was no way to sell videos and by the time the VHS and DVD technology came out the demand for this had dropped tremendously.

Remember also that when live lps are issued they usually are edited from several performances to make one great show. Video is a little harder to do that.

Also keep in mind that Motown only capitalized briefly on the parting of Diana Ross and the Supremes. After Diana's first solo release all Diana/Supremes recordings were halted for several years. Once Diana was established as a soloist, and it took three full years to do this, Diana/Supremes complilations began to appear.