People do buy however on the small shards it is just slower. Like I said, I sell on both Atlantic and my home shard. I generally sell cheaper on my home shard due to the slower sales, more for reducing the impact of vendor fees than for the fact that people won't pay the full retail price.
The OP was suggesting that the fees were killing small shards, and they are, due to the slower sales. I don't agree with no fees, just a more balanced system where the fee is based on the amount of the item you are selling rather than the time it takes to sell. I might not sell a plant on my home shard for 3 months, then I go one day to find that the plant vendor has sold out as someone had decided to redeco. It is the same for imbuing ingredients, may not sell any for over a week, but then all 'essence of order' sells out as someone decides to do imbuing and needs it. If I have stuff that after 6 months I have sold NONE of then I don't continue to stock it. However I tend not to stock stuff that doesn't sell, it just takes a lot longer to sell it on my home shard than on Atlantic. The longer something takes to sell the more vendor fees you pay, so not only do you sell stuff cheaper anyways, you also pay more in fees. If they turned vendor fees off (not that that is what I recommend or think would happen) and the stuff just sits there is actually NOT a problem as it isn't sending you broke.
I sell rune books on Atlantic for 5k ea, I sell them on Oceania for 5k ea. I will sell 30 books on Atlantic in a week, and 30 books on Oceania in perhaps 2 months. It doesn't matter if I drop the price of books on Oceania to 500gps I would still sell the same amount as it is not the price but the demand that determines the 'sale'. The only difference is the profit on atlantic is 143,700 (30 runebooks x 5k ea incurs 30 x 30gps x 7 days = 6,300 total fees), to the profit on Oceania is 96,000, ( 30 runebooks x 5k ea incurs 30 x 30 gps x 60days = 54,000) the only difference being the time they take to sell.
Because of the slower sales and vendor fees what is happening is that people give up on even bothering to sell anything on the small shards. A flat fee means we all pay fees, just it doesn't matter how long it takes to sell. If I have 30 plants on my plant vendor at 5k ea (total worth 150k) in 3 months ( say 93 days) that is 83,700 gps I have paid in vendor fees on those plants. If I then sell out I make only 66,300 profit. If on the other hand it was a flat fee system, on the above example items under 50k incur a 1% fee so at 5k per plant that is 50gps 'fee' per plant. On 30 plants that is a total of 1500gps and I make 148,500 and it doesn't matter how long they take to sell. It means that I can afford to stock really cheap and low end items at no loss. Obviously the greedier I am and the more I charge then the more fees I pay.
Vendors on small shards are not encouraged to sell the 'every day' items as there is little profit in it. The complaint with a lot of players on small shards is there is nothing to buy, that is why. On my furniture vendor I stock 'anvils' and 'small forges' and I might sell one of them every 3-4 months to a restarting player who doesn't have a crafter yet. By the time that anvil or small forge has sat there for that long I am probably making about 20% of the original price I posted it for, which probably doesn't cover the cost of the ingots to make it
A flat fee would eliminate the problem.