I don't see why they'd remove them, you only get the first 2 tiers at the shops, and while the first tier is like 2-4gils for the mats, the 2nd tier is already like 20-30gils for a lot of stuff, which you can already undercut and sell easily if you've been leveling gathering on it. I collected abnout 300cotton balls when I was lvling Botany and I used up all that getting to lvl 20 weaver, iirc balls are 8gils each(they're fairly cheap in comparison to some other stuff) so that's a decent amount. Tiers after that you can't get at all other than gathering so that's when the prices go up. During the last day I sold my excess of Yew logs, which is lvl 20 botany shit and it sold at 50g a piece, made 4000g out of like 10mins of farming shit for HQ mats. I also sold one fo the book I failed to HQ, lvl 20 one, vendors stop at lvl 15 weapons, it sold for 800g even though it took like 40secs to craft and only used maybe 150g worth of mats.
There's definitely big bucks to be made on crafting/gathering I think but I probably won't bother too much. Also if you want to really high lvl craft, you probably don't want to sell mats. You need an insane amount of items to craft to unlock the achievement for the best crafting weapon. Basically it's like 50 1-10 items, 300 11-20 items, 750 21-30 items, 1000something 31-40 and like 3500 lvl 41-50 items. Not sure about the numbers but it's that sort of shit, so at the very least you'll want to keep everything past tier1. I wonder if quick synth counts though, could probably just buy a ton of cotton and quick synth it then resell the yarn for cheap to recoup a few of your costs.
