No. There are only 6 mats in this game, 2 of which are legendary and should not be bought so easily. Other games have hundreds of different mats and no one really complains about having to farm for them.
Yes but those games have a higher drop/find rate of said items. So buying them wouldn't be needed. However destiny has a much lower and much more random drop/find rate making it much harder to level up gear. While I don't think buying the mats is a good idea I do think that some sort of compensation of regular mats should be allowed. That or the spawn rates of such mats be changed.