at £75 for 30 greatswords you can bet your bottom dollar that fantasy is profitable lol!!!
whether its gamer legend or not i dont know, but the legend goes that space marine sales are well over the entire fantasy range put together.
if true, it tells you a lot about the spread of gamers between fantasy + 40k.
i think GW's pricing strategy puts a lot of people off starting fantasy. outside of super elite armies, it costs a small fortune to start a new army, especially given that basic troops are around £20 a box and you'll probably need 3-4 of these even for your cheapest, shittest unit; let alone your general, elites, cavalry, chaff and artillery choices on top of that.
that said, GW have invested a lot in WFB over the years, all the molds, copyrights/trademarks etc would be worth a lot. i suspect they'd rather reboot and keep that value in-house than sell it to someone else and effectively create a new competitor, especially when flames of war, infinity, warmahine/hordes etc are all gaining in popularity