I see open-source as being a free teacher. You don't have to support anything! If you want to use the code you'll have to figure it out. Closed-source is like hiding free knowledge though... it's bad! And gaming is full of it.
Software you are praising of releasing open-source software are just that companies that you are pointing that finger, releasing before closed-source programs, and are able to distribuite free their source code just because they already earned the money (directly from it or from other sources) and/or the software is already an old technology / not competitive (aka not profitable).
Firefox is open-source, but they earned $421.3 million just in the 2015. id software released Doom source after many years, with one of the reason that it was an old tehcnology. Wordpress is one of the most famous open-source software, the company is a non-profit organization, so they are eaning revenues through donations made by individuals, that could be a person like you, or a large corporation that are making money from the platform through advertisements.
I do not think there is someone that released an open-source software without the intention to earn money from it in the first place (of course not counting the little copy-paste software you made in just a weekend). Who are these people that released open-source software and did not make any profit?