The reason "The Drew Carey Show" is not coming out is NOT due to lack of sales.....it's music rights costs. This show, along with "Murphy Brown" are the reasons Warner Brothers stated on an online forum back in 2008/2009. There are alot of music segments in both shows and WB didn't want to pull a "WKRP In Cincinnati - Season One" move by replacing music. Warner Brothers has stated that it is too expensive to get the original music rights costs for the show to make on DVD. (Basically, costs to get the original music would outweigh the DVD sales).
I really love "The Drew Carey Show" and wish they would least come out on WB Archives a season at a time, but I guess the music industry has a hold on this show!