It's a crown sink. Crowns are generated every time a person enters the clockworks, they are infinite. The only crown sinks in the game are buying recipes (and equipment from vendors... but I don't know ANYBODY that does that), crafting, UV rolling, the 10% AH tax, the 2% CE exchange tax, and the downright chump change charged for entering the clockworks at Tier 2/3 or joining PvP. If crowns are not taken out of the game then you just see continuous inflation, we're talking things like CE costing 20k for 100 and a 3* piece of equipment costing 50k.

It is 10% to remove crowns. And there will always be people willing to pay pay the 10% to sell an item fast and people willing to pay the extra the sellers tack on to make up the profit they'd lose otherwise.

~Gwen

I recently spent 5 hours trying to sell a Skolver Coat recipe for 30kcr {...} Now I simply do not understand why on earth 10% of my earnings must be taken.

Because most people think their time is worth something. You saved 10% of 30kcr, or 3kcr by spending *five* hours trying to sell the recipe. In that time, I could have made many trips to basil, earned a bunch of crowns, gotten a bunch of mats that I could sell on the AH and quite a few recipes. Yes, those mats that I sell on the AH will also have a 10% cut taken, but compared with most people who just let their hoard of mats build up, I'm getting *something* for them.

Even if the seller fee at the AH was 20%-25%, it would still be a huge savings to me over trying to sell via spamming. Oh, and I also understand how annoying selling spam is, and I see no reason to be rude to so many people.

(...) but look at it from my POV if I sold that Recipe for 26000 at the AH I would've got back around 24600 cr which means that I would've made a loss. I finally understand why there are people selling stuff for cheaps outside the AH.

That's why you don't set (and see) buy it now prices less than 28K for 5* recipes in the AH. I've seen the buy it now price drop below the point where you are basically selling at a loss in lower than 5* recipes, because going in lower tier Basils is much easier and there allways will be someone that doesn't do their math correctly (or is desperate enough) and set it to sell at loss, but 5* recipes sell fot 29-35K in AH, allowing for a nice profit margin despite the 10% fee, so why the grievance?
And BTW, if you sit on the recipe for a day or so, so it falls off the Basil's offerings, you will be able to sell it higher as supply diminishes. Basic economics.

Also, most people have job/school and life outside SK, and hanging around out of the AH trying to trade stuff is not an option. So, AH actually offers a good service to those people.