But you can't do anything to stop anyone because there is seller and there also buyer and they agree on each other.
This, pretty much. I never even knew animal trafficking in Animal Crossing existed until I got ACNL. xD
It's considered "taboo" and "terrible" in comparison to real life because it's
not real life. It's just a game. It's supposed to be fun and games and happiness for everyone. And anyway, nobody likes to be scammed.
Truth be told, if the market didn't exist for dreamies, I wouldn't participate in it. But as it is, buying villagers is the easiest way to get them, and selling villagers is the easiest way to get bells to buy the villagers. It's a cycle.
It's just incredibly greedy on the seller's part and stupid on the buyer's imo, especially since you're essentially paying potentially millions of bells for a character you may not even like, or that may not even stay.
I think you need to look at the circumstances. There are some sellers that sell villagers not for profit, but for a chance to buy the villagers
they want. Sometimes it's hard to weed out which is which. As for the buyers, you can't judge them for being stupid right off the bat if they know what they want when they buy it. Most people who buy for high prices actually want the villagers they buy to stay forever. No one buys a villager they may not even like.
Please be careful when speaking like this because it is generalizing like pretty much everyone in the villager trading market. You don't know why they do the things they do, not everyone is automatically "greedy" or "stupid".
I really much prefer trading villagers to selling them, however I believe selling them is the safer option for everyone involved. For example, someone tries to trade Beau for Ankha, and Beau needs to be taken first because Beau's town is full. The other user promises Ankha and takes Beau first, but never gives Ankha. The first user is essentially scammed out of their villager. When dealing with bells, you just have people drop the money, they go adopt and that's the end of it. The payer even has the option to check if the villager is really in boxes before doing the transaction.
As it stands though, I've traded/given away villagers more than I've sold them. I've been scammed out of good villagers twice, and I wasn't "greedy" with either one (tried to trade for villagers I wanted instead of bells). Can't exactly blame me for preferring to sell villagers in the end. Nobody likes to be at risk of being scammed.
I haven't bought any villagers though. Well, besides Willow, but the person wasn't selling them. I just gave them bells because I felt bad taking Willow for free. xDD; But I'm pretty sure if I ever buy Marshal for 40mil I will be keeping him forever. So no, I don't think that makes me stupid for being a buyer. I just do what I like with bells I earned by myself.