Because Bethesda's games always require a shit ton of mods to be playable so they are basically charging extra for OTHER PEOPLE'S WORK just so people can actually have a decent game in addition to paying 60 dollars to even being able to mod it in the first place? Bethesda also has very little involvement in mod development, most of those people do that out of their free time, with no budget and just for passion, so for Bethesda to then claim they are entitled to receive money for that is preposterous. Also they offer no support to modders at all, a lot of them have to inject new scripts, patch the game so it actually uses more than 2 gb of ram and develop mod organizer tools, all of those things are ESSENTIAL to get a modded Beth Fallout game running, and they aren't found in the Steam Workshop. With all that lack of any real involvement, or even basic support they are still asking for 70% of the profits of the work of others. Tell me how is that even a good thing? If they actually wanted to help modders have a legal way to get money for their work maybe they could start by not treatening with legal action to those that try to set up donation campaigns? Nexus offers a more direct way for people to support modders through the Donate button while ALSO offering all the necessary applications and support for free.