Why Steam is still best place to release game for indie devs?

If you are a small developer with little budget you need to do clever steps. And especially in the field of marketing and game releases. You can read a lot of good marketing advice on the internet. Many of them are valuable (as to have a marketing budget at all - you really MUST have a marketing budget, no matter how little your total budget is), but many other are rash or, at best, they don't work for every dev on the planet and they should not be used without reference to your own situation. And this one is particularly tricky - surely you've heard many times that "Small indie devs should release their games in as many online stores as possible".

Well - in practice this is not entirely true. Unless you can afford to employ a few people full time only for making publications - you should focus on 2-3 markets that are most promising. Focusing on too many targets distracts you and makes it difficult to make best results.
Publishing in too many places has significant flaws:

1. If you don't focus on one place, you will get mediocre results everywhere and it's better to try achieve a good result in one place.

2. If an online store wants to promote you - that's good, but otherwise it should have a really huge user base to be profitable. If there's no promotion and no huge user base - your game will have an audience close to zero.

3. They say that point 2. is not very important because any sum of money is good for a small dev. No - it isn't because most of online stores have withdrawal limits and in many cases your sales will be even below that.

4. Publishing in every store means extra work. It's amazing how many form fields is often required to submit a game, but it's perhaps more surprising why the hell all of them use different sizes of graphical assets. Sometimes sizes are so exotic that you need to repaint your assets from scratch because there is now way to rescale them. All this work is heavily unprofitable and small dev team have much work that is more important to be done.

5. Most users of these stores are already users of Steam. This mean that even if there will be some sales - they only cannibalize Steam sales, and don't increase overall sales.

Many of these small stores only mimic Steam and offers nothing more than it. Surely Steam is the leader and the trendsetter but if they want to be competitive they should find their own advantages. For example they could do more promotions for small devs or at least mimic Steam assets sizes (!) to make their submitting process easier. On the other hand Steam, even if it's flooded by games this year, is still a store so big that it generates sales even from random visitors and provides a decent revenue even if you fail in marketing field.

Taking all this into consideration with our new game (here it's a time for a small self-promotion: Lemuria: Lost in Space, try it - it's really good :-) ) we decided to skip publication in most of small stores and to focus on Steam with a small exception for Humble Bundle store (which we will try experimentally to see whether the sales there will be good) and Amazon (which historically provided us decent sales, has low charges and no withdrawal limit). For stores like Indiegamestand.com, Greenmangaming.com, Itch.io we don't predict sales large enough to be profitable. GOG.com looks like a store that whole sole purpose is to sell The Witcher 3 (which by the way is a really great game,
we all love this game) and Indiegala.com purpose is unknown, perhaps it's just cheap for them to have a store when they already have a popular bundle site.

TL;DR: We are a small team and we need to focus, so publishing in a large number of stores is not for us. It looks that Steam is the most profitable way of distributing a game and distracting on other stores is only a waste of time, money and other resources.

Do you agree with our point of view?