with 15000 mating nuc's look at it this way, say they sale (im not sure of their prices but these are examples)
(THESE ARE EXAMPLE'S, THEY COULD SALE MORE AT HIGHER PRICES, i AM USING THE LOW SIDE PRICE)
2000 packages W/QUEENS @ $45.00 = $90,000.00
13000 QUEENS @ $12.00 = $156,000.00
FOR A GRAND TOTAL OF = $ 246,000.00
Not a bad year and that's if they load their mating nuc's just once
now they might sale more or less in both categories but you get the idea, and not to bad of money for working for yourself and doing something you love, then expenses and labor hit but I would think they sale more queens than 15000 a year especially with all these hives dieing and disappearing...
Even after that they still do get honey and some pollination on top of the prices above, plus probably sale wax and pollen so add that in......