I don't see why not... Costs are over for that figure beyond reproducing it, which is minimal, so it'd actually be in their better interest to satiate demand unless you mean they'd be better off selling it for $4.99 a piece and make $15 as opposed to $10 for 3?
I think the thing is though, they'd sell MORE of the $10 than they could of the $15 / 3 individual figures... The single pack would take up less space, wouldn't interfere with case ratios, etc., and the figures would still be generating more profit than ever really.