It’s a concept that works better with large herds, like on the savanna. They’ll run a herd and pick off the weakest. I agree in BC that it’s much more opportunist. Animals are more widely distributed, they try to kill whatever they come across e.g. a lone healthy moose is fair game. The snow pack conditions, when deep and crusty, essentially make all big ungulates ‘weak’. Given the choice, they will predate on weaker animals preferentially, not out of some Disney law, but because their success rate will be higher, energy output lower, and the chance of injury less. They are the ultimate gamblers, great at reading odds and the players at the table.