Clearly if someone can’t afford things like video games or a pass to Brony Con, it’s time to stop relying on art and go look for a better job
If an event comes up that would be very beneficial to your business, you go to your employer for help with attending that event. If issues come up with the means that you use to do your job, then you go to your employer to see that those issues are resolved. For an artist on tumblr their audience is effectively their employer, to whom they’re oftentimes providing free content. If the artist wants to give their audience a means to supporting them without requiring it then more power to them If money is freely given then it’s up to the artist to determine how it’s used, and more often than not it’s used as it should.
I don’t know who the original anon follows that holds donation drives and explicitly says that it’s for a videogame, but most calls for donations that I’ve seen have been for either emergency situations, or for the benefit of the artist’s general financial situation. If they have donations open outside of specific drives, who cares? No one is making you donate, or even look at the button. If you donate, then congratulations you’re supporting someone whose content you enjoy and want to see more from. If you don’t donate, then nothing happens to you, or to them and things go on as though you never saw the little donate button in the corner of their blog.
All that aside, if you’re going to judge someone for having the option available to give support at your own discretion, when that person provides free content it doesn’t matter whether art is their job or their hobby. In that situation, you’re the issue and should frankly piss off.