I want to add myself as a data point for you. I don't explore games (or apps) in the Play Store, because 99% is crap. Randomly picked app/game is something barely functional and evidently made for ad income. This makes me install only the reputable apps (like Dropbox, Acrobat Reader) or ones that were recommended by friends, on HN (I've bought an app just this month from a recomendation here), or somewhere else. As for games, I don't shop for those often on purpose, so unless someone suggests it to me, I probably won't find it. PC games tend to be easier to encounter, I have more avenues to check their quality before installing, and... there's this feeling that I have more control over what I install on PC than on my phone.
PC is more organic as there are a ton of stores and steam itself promotes game discovery as friend's games are visible.
I'm one of those DotA playing guys who loves small indie games (try to start working on one.)
I'd also love Brothers if it's still available :D
You can add me on steam if you feel like: http://steamcommunity.com/id/amxn
(i am "fat0wl" on steam too!)
It may just be my personal prejudice based on my friend-group, but my impression is that there are a lot more people on PC willing to seek out, try, and talk about unusual/obscure games. More people on mobile tend to get their game recommendations from the "Top Paid" and "Top Free" lists, and if you're not Angry Birds or Minecraft Pocket you're not likely to have a lot of people notice you.
Not that PC gaming doesn't include a huge contingent of people mainly play the big releases (CoD etc), but even among my esports buddies who play DotA all the time there's still a lot of excitement about smaller studios.
EDIT: Speaking of, anybody want a copy of Brothers: A Tale of Two Sons? I picked up a couple of extras during the last Steam sale to give away since it's not nearly as well known as it ought to be. Difficult to describe by genre, but I might call it an interactive fairytale? Requires a controller (each thumb stick controls a character).