I never minded having extra clients so much... just the way Epic is doing their business. But even if they hadnt gone with all the poaching of exclusives, I wouldnt use their store, because I reached critical mass of accounts and clients. Let's dive into that:
WoW/BattleNet: thats where my usage of client/accoung-based gaming basically started. I was so used to having to use CDs/DVDs to play games, and when I started playing WoW in 2007, I really liked that it just didnt need the CD to be in the drive... and when they launched the BNet client, I used that almoist instantly. I have some other games on there, but only play WoW.
Steam: thats where I keep the majority of my games and play them. Started using it in 2011. Wasn't happy about it first, but I needed an account to play my retail copy of Magicka, but soon noticed that it's a great client and the store with regular sales convinced me to keep using it. The constant influx of updates and new features just makes it the best there is, by a countrymile.
Origin: also started using that in 2011, when it was still called EA Download Manager, I noticed I could activate my retail Dragon Age code there and I wouldnt have to use the DVD, so I started using that back then, and have played EA games on there every now and then over the years. It's however not a great client, and the library is super slow. I prefer not having to use it. Their subscripting service is a good offer, but not for me, ultimately.
UPlay: when they started UPlay, it wasn't great, but eventually it got tolerable and I have pretty much all my Ubisoft games there. If only for the main reason that Humble, Fanatical, GMG offered UPlay keys and those places are where I generally buy games. Then at some points I had enough games in my UPlay library to justify buying directly from their store (the UPlay points 20% discount is nice, too). I do like Ubisofts games to some extent (AC:S, FC4, Rayman Legends, for example), but I really dislike their rampant greed.
Windows Store/XBox client: I had a MS account for years for some reason, and I tried the new Xbox client. Its okay. I like their subscription offer, but its not for me. I prefer owning my games.
BethesdaNet: a bad publisher with some great games by its studios.. Its really weird that they decided to use their own client for their small library of games. Well, at least they get released on Steam, too. I wont be using that client since its on par with the EGS in terms of how useless it is.
I do have a BethNet account since I used their forum once or twice (especially when they decided to apply German laws to Austria and released Wolfenstein New Order censored/regionlocked here....)
GOG: good store, mediocre client, Galaxy 2 is a good idea, and I hope Steam will shamelessly copy it somehow
. I dont buy many games there though, just older ones that didnt come to Steam yet, and I usually purchase them again on Steam once they do.
I recently switched back to Linux anyway, and all of these services - except Steam of course - don't have Linux clients, but BattleNet runs fine thanks to WINE/Lutris. It's worth pointing out, to those who dont know, that Steam offers Proton which enables Windows games to run on Linux, and so far most of them ran just fine. But I'm not sure if I would wanna jump through hoops to get UPlay, Origin etc to run just to play their games.
EGS has shown me and plenty of others, that there are always more games to play than we have time anyway, and missing out on a few particular games isn't such a big deal. Well, thruth be told, that was clear for me for a long time anyway. I always hated exclusivity, including first-party-exclusivity. I had considered buying a PlayStation plenty of times, usually when highly praised PS-exclusives came out, but I haven't given in so far, and I don't think I will. As good as those games might be, so many more good games exist on PC. And the same is true for EGS: regardless of how many exclusives they secure, as long as they dont find a way to actively remove games from my Steam account (and I believe if they legally could do that, they would. For that matter, I am curious how they will handle Rocket League on Steam later on) ... then I do not see any reason to buy anything there. And I hardly see any reason to support developers/publishers who took their deal and later release on Steam. I don't need to reward that behaviour, these people aren't my friends, and if they sent me a clear message that my purchase doesn't matter to them, then so be it.