back in 70s and early 80s, some would take away that bottom head to avoid that "funky" tone.. if you notice old records, the toms would almost sound the same with other records.
Phil Collins didn't have the bottom head too. But if you look closely, you'll notice that his toms never did accommodate bottom heads,..there were no lugs at all!
at present, I'd still see a few drummers removing the bottom heads. especially drummers in church whose parents played in a band in the 70s. I asked them why they do it, and I simply got..."hindi ko alam...hahahaha!".