Steams core customer is the game developers/publishers, who they take a ~30% (last time I checked) cut from the profits from.
The people who buy games are simply users of Steam, and Steam has to treat them well, otherwise their actual customers (developers/publishers) won't get as much profits, and indirectly Steam.
You could even say that steam is a customer of the developers (I buy your game at x to sell for y), and the average person is a customer of steam and the devs.
I don't really see the customers or the developers as the core. Both groups tie into each other in a big network effect.
If game developers and publishers could get the same audience without steam and the 30% tax, they would in a heartbeat.
They'd probably cut the price a little to expand sales and enjoy the wider margin. Margin that could be spent on salaries and growth.
Thankfully Valve is investing its proceeds in developing competitive products that enrich the industry and not just skimming.
30% of the price is distributed to Valve instead of developers.
Whether that results in developers obtaining lower profits or users paying higher prices is entirely subjective; that depends on what would happen otherwise, which is categorically unprovable.
If it's a point of issue between me, Valve, and the game developers, at the end of the day it's my decision that matters because I have the money and if I choose not to spend it the whole thing stops working.
Take away valve and then I go straight to the source and purchase games from the developers directly, it's going to be inconvenient, but it'll be fine.
Take away the developers and valve will fund game development and start making their own stuff like Netflix has with all the media companies.
Take away the customers? Game over.
Of logic works all right when you're talking about Google and the fact that the advertisers are the real customers, because of the end of the day the advertisers have the money and when it is advertisers versus users the advertisers always win.
It's important to be the guy funding the system at the end of the day, otherwise you get screwed.
No really, the developers have 30% removed from a sale which goes to Steam. People who buy games don't see a price + 30%, it's the developer who sees the fee when they look at the sales. Otherwise all receipts from Steam would be $GAME_PRICE + $STEAM_FEE, but it's simply $GAME_PRICE and then the developer when looking through their sales, that see $GAME_PRICE - $STEAM_FEE.
This is not me as the user paying. Gotcha.
The customer pays for /everything/ /always/ under /all/ circumstances. It's not cost plus pricing, vendors will charge as much as the customer will part with. Customers are willing to part with less when competition pushes prices down. That 30% is definitely keeping prices higher to the customer in any remotely competitive market. (I say nothing about whether that is a good thing or bad, whether that is cheap or expensive - it's just nuts not to know the customer is paying it, that's whose pocket the money comes out of).