In a way yes, depending on how you define earn. Consider that in order to purchase these things from Xur, you have to earn the strange coins. Typically this means you've got to get through a weekly strike (other methods are available but the rate of acquisition is very slow). There is the possibility you got carried through the strike. If you did, then those coins were not earned. If you contributed equally or more than your co-players, I would say it was earned. Just like although drops in raids and other events are random, if you played well and tried then perhaps we can say you earned it. It is of course disappointing to see a player who worked less hard or not at all get better drops than you, and they certainly didn't really deserve that drop over you if you contributed more. But to some degree they can be "earned". In other aspects there's no logic to it at all (this concerns mainly drops).