If you really have a problem with this system, completely ignore the microtransaction system and treat it like, well, the vast majority of games without microtransactions.
So, here is your new game:
The skins, voice lines, poses, sprays, etc. are no longer purchasable with real money. You have to unlock them by leveling your account through playing the game (just like every other game with unlockables).
You are unlikely to get the "best" skins and such as drops, because they are the equivalent of rare loot drops like in other Blizzard games (i.e., Diablo 3 and WoW).
While it will take time to "buy" the best skins with the coins you get from dupe drops, at least you have that option. If it's a pose or voice line you really want, they are a little cheaper, and you can target one of them easier (I left out sprays, because while some are kind of cool, can't imagine many people really care about those).
There, now the game has no microtransactions if you just ignore the little store icon. Unless your REAL problem is that you are jealous that someone was willing to spend money that you aren't to look or sound "cooler" than you are able to in the immediate future. Afterall, "he" didn't have to work for it (in game, that is), so why should you?
edit: On a side not, I strongly support these type of microtransactions, because I realize there is no way Blizzard could justify extended support (as in greater than a couple of years) with maps, characters and server uptime if they had no more money coming in.