Destiny isn't the type of game where you can just not download DLC's and still play with 100% quality, nor should it be. The purpose of destiny is to adventure and expand with it with every new coming expansion. Besides, if your "friend" can pay for PSN, then he can pay $20 more. And it's not like you have a time schedule to buy the expansions, so I'm sure that at SOME point in his life, he can pay $20...