To produce their wax, bees must consume about eight times as much honey by mass.
mean of 8.4 lbs according to Whitcomb (1946)
And, One pound of wax supports about 22 lbs of honey. (From Beeswax Production, Harvesting, Processing and Products, Coggshall and Morse pg 41)
Therefore, spending eight pounds of honey, nets 22 pounds of honey storage. Thats a 36% difference but it's also not including the capping wax lost if you extract. We might be able to drop that to 33%-35%?
Consider also that Whitcomb (1946) found a tendency for wax production to become more efficient as time progressed. A hive raised on crush-and-strain or cut comb may then produce wax even more efficiently, maybe down to a 20%-25% loss?
Figure in your expense for extracting, time difference including setup and cleanup, equipment depreciation and my calculator just fried. :-D :-D
I'm GUESSING that there's a harvest volume in there somewhere that "justifies" extraction -vs- comb removal...
I'm hoping that someone can provide more studies beyond the two above that I "borrowed" off of Michael Bush's web site.