Yeah, so umm, gacha as an investment is a poor copium. 1) It's not material. There will never be a return on investment and the game itself won't grow in value to match your support. At least not in a way like stock or any other actual investment. It doesn't even have to be traditional items like stock. A physical trading card game is an actual real investment. As are collectibles from comic books to action figures to literally whatever is a physical item that someone has to produce. 2) So yeah, the only return in investment you can get from a live service mobile game, is going to be in game content. If you truly enjoy playing the game a ton this is a solid reason, but still paying more than your rent is... questionable. Especially because there's no actual breakdown of how much of the money goes into this game directly vs the company's coffers or into other games. There's also no guarantee the game will continue to even exist. Unlike a single player or offline game you'll always have access to, these gacha games are to the whim of the company. At any moment they can pull the plug and move on and all the money you've invested is lost. You can't even say you got a return on that investment in the future entertainment value you'll be provided by buying those items. It'll just be all gone. 3) Yeah, for supporting the devs... it's again not clear where that money is going. Most of it is probably just feeding into the chief executives that everyone hates. The people who build the game you love and whom you want to support, are usually not the best paid. Regardless, they'll always be paid a fixed salary based on their position. I feel the most sorry for the artists. In comparison, it's not uncommon the CEO or some other higher up executives to have bonuses written into their pay based on the company's performance. The shareholders are happy when they get a little extra scratch and they pass that onto to the people at the top. Its unlikely for this to trickle down. Really, it wouldn't even make sense. A company might use their extra money to build up by hiring more workers or reinvest in themselves to grow, but there isn't much reason for them to give a big bonus to lower level employees. Some companies might have similar bonuses related to sales targets or milestones to motivate workers, but that's not super common.
That's all to say, yeah for the most part that money would serve as a better investment being thrown in a pit and torched on fire. At least then it might warm you. Spending as much on a free to play gacha game as you might on one or two full priced games a month because it gives you similar enjoyment is one thing. Spending as much as you would on your rent presumably frequently is a whole nother