Again, you're talking about a wildly profitable service that posts year over year growth that would make any company in any industry envious. When you say Steam, you are talking about over 70% of the PC digital distribution market. When you talk about Valve, you're talking about a company founded and still primarily owned by an exceedingly rich man who enjoys gaming and feels privileged to work with the people employed at the company. Valve is the fourth largest consumer of internet bandwidth in the world.
What sort of catastrophic massive collapse of gaming as a hobby could result in a company making strides in bringing titles to Mac and Linux deciding one day that it was going to take its ball and go home? Talking about Steam like it is a Geocities site is more than just a little silly, it shows a baffling amount of ignorance about the business world. Their work in game development, and their work in bringing Steam users the ability to actually make money using the MannCo store (which some users make something along the lines of half a million dollars a year profit off of) has bought them immense good will with their customers. Which is not to mention the massive sales and over 40 million users with active game libraries. These things cement their place in the games industry, if something catastrophic happened to Gabe Newell and his children decided to liquidate his stock (provided he has not already made some sort of other arrangements) any company in the world would love to acquire such a massive worldwide distribution network.
This notion people have that Valve is going to go away and Steam will just have been a bad dream is ludicrous, if you refuse to acknowledge that digital distribution is on the rise and that a huge portion of that industry is dominated by Valve and Steam then you really should do a little research. When someone says they feel Steam needs competition, I can understand that. It's not healthy from a business perspective to let one company become monolithic and dominate the industry. However, there's one huge problem with that. The only competing services are run by idiots who are trying to get you to pay ridiculous sums for old games (Origin, Impulse after Gamestop purchased it) and don't care one whit about their customers.
Valve on the other hand isn't content with standing still and resting on their laurels, they constantly improve an already exceptional service, Steam Workshop is just the latest bit in a long line of tools they give to developers so that they can add value to their products. Where another company would have cornered the market on virtual hats and laughed maniacally while petting a fat cat, Valve opened the Mann Co store up to customer generated content, where people could create and profit from their own virtual goods. Even when Steam was getting started, Valve didn't force it on anyone until it was out of beta, I ran Half Life 2 without ever installing Steam until they invited me to beta test Team Fortress 2. And upon the release of the Orange Box they gave gamers Team Fortress 2, Portal, and Half Life 2 - Episode 1 for a reasonable price, knowing that some might feel that Steam was an onerous service. My point being, if Steam is going to get serious competition, it might ought to be from a company whose last CEO didn't have running Sara Lee Bakeries as his primary qualification.
That was a bit of a rant, but I've come to hate having this conversation with people who use misinformation to communicate a point that boils down to "I don't like them", that's fine and no one is saying you have to like them. Personally I too feel like someone should do as good a job as Steam at making customers happy with their service, Steam could use some competition. I just can't stand when logical fallacies or outright flagrant falsehood is used to support any argument at all. You're on the internet, Google is there to give you actual facts if you care to try to work them into your posts.
When you effectively tell an indie developer that they should ignore 70% of the market because you dislike a company, that's selfish and silly, encourage them to branch out and find as many methods of distribution as they can. Every sale is helping ensure that a company you support has a future.