Andrew: There's a lot to think about here, and much of it depends on what you enjoy doing. If you like the idea of owning and running recording gear, investing in your own is a good idea. But keep in mind that you may be the person running the gear AND playing drums. With someone else running the gear you can just focus on being the drummer. Now, doing both is OK if it's what you enjoy. Lots of guys play and record their own instruments all day and can barely stop to eat because they're so passionate about it. If that's you, go ahead and invest in some recording gear. (I've been doing that for 40 years.)
When you lead a band you learn how to handle money, how to be a salesman, and how to cope with difficult personalities. You may decide, like many band leaders, to purchase the sound system and microphones, and make an agreement with the members that you take a double cut, or at least pay for repairs before dividing the money. (Each member owns his/her personal gear - instrument, amp, etc.) This way you can be sure of the sound system's quality and upkeep. This is good if you're committed to running a band, even when the members come and go. What often happens is that 2 or 3 members tend to get along well, and become the core of the band. Together they make decisions about who to hire or let go, even though the final decision may be left up to the leader.
At your age, the band really isn't a business yet, and band members are friends. Friendship is probably a higher priority than it would be in an adult, professional band, and this is fine. But at some point you may find that one person is not fitting in musically. You'll have to make a choice, and you might harm the friendship if you let him go. You'll have to decide what's more important. At your age, though, try not to take things too seriously, and just have fun.
As far as your poor friend: It's best to come to an agreement between all band members concerning what is expected of each. The band may vote that each member must provide his/her own gear, and at a certain standard. A member's spending habits is his own business, and should not be discussed at all. Either he goes along with the majority and buys decent gear, or he's out. Now, if your friendship is important, you may decide to loan him your gear, or buy something he can use, which you will keep. Consider it an investment. When you're dealing with people, there are no perfect answers. Best wishes.