Why is win trading such an accepted part of this game?

[Jetstream_Fox]

Uh, people pay for carries all the time... effectively the same thing.

Not really. This "win trading" as people are putting is nothing more then boosting. Getting 100 wins through illegitimate ways impacts the rankings that SE has implemented for The Feast, granted it's not really a huge impact since they will be reset each season. Boosting still leads to devalued views on content, which in turn leads to less people actively participating. Typically games that use seasons and standings usually match players with or around the same skill level to ensure quality matches. When a player boosts for their levels and go and play normally after obtaining whatever they wanted, it puts the team in disadvantage having to carry someone who claims they're rank 50 but in actuality they're rank 23. I don't think The Feast and SE use standings like this but this is just one example of why win trading or boosting is bad.

As for buying a clear, you aren't messing with ladders or global rankings, since raiding and dungeon runs aren't rank or timed for completion, nor are you being matched with random players when it comes to buying a clear.