Free to play games need to make money. Selling a few characters as exclusives to people that want early access to them is one of those methods. Surprising that you decided to complain about wedge when there are many more unobtainable characters behind a pay wall. (sure you could farm 500 crystals form getting #1 in arena everyday, which would take around 2 months of doing so, assuming it takes 30k crystals to 7* the character, and that you do not spend those crystals on anything else, like refreshes, which are much higher a priority)
Selling things in a gatcha styled way is a very good way to get people to spend, as it increases the reward/satisfaction a player gets when they get lucky and pull big. You can make a perfectly viable team without it, not a single premium character has ever been a part of any meta so far, and even if it were, plenty of other teams can do just fine in arena.
Look on the bright side, they have never released a remotely interesting or cool character in aurodiums, always secondary characters, although there are still some fans of these, they have not released Jedi luke yet in them =P