Sure, it happens frequently in other games, and it happens frequently here. But that doesn't mean that there are game systems for this elsewhere, nor does it mean that there ought to be game systems here for this.
In WoW, I know of no mechanic that allows for what the OP is requesting. Nor do I know of any such mechanic in EQ or EQII or LotRO or AoC or DCU or CO or STO or... actually, no games do that, that I know of.
This is utter nonsense. If you engage in a trade with another character, and they somehow found a way to hack the game and force the trade window to cheat you... then sure, devs would step in. But if you get a random stranger to promise to make you something, and you send that total stranger some materials in advance, and then that total stranger rips you off... it's all on you. It's up to you to make sure that your trades are fair. That's not the devs' business, nor should it be. They have other things to spend their time on, besides mediating between parties in trades.
The bottom line is always CAVEAT EMPTOR: "Let the buyer beware". It's your responsibility to ensure that you're happy with the details of the trade. And again, other than hacking or other explicit cheating, the devs have nothing to do with this sort of thing, here or in any other game.
Hardly. I've played over two dozen MMOs in the last thirteen years. At no point, in any of those games, have I felt that it would be wise or prudent to send cash or valuables to a stranger. In all cases, I either dealt with friends, or over the AH, or arranged to buy a finished product (for which I might pay cash or materials or some combination thereof). And I've never experienced this as a problem; I'd do the same in real life, after all.
I'm genuinely sorry the OP went through this. I'm not being callous; I don't enjoy the suffering of others. But the OP was foolish and the devs are not responsible for that. Sorry. Next time, please be more careful. That's all that anyone can offer you here: good advice, well intended.
This is a joke right? Its an MMO, trade is what makes the economy go around, and we need trustable crafters to make that economy work, depending on guildies to get the crafting recipes would either take forever or everyone would join the same few guilds just to get the trust of the only few ppl on the server who have the recipes, so with your logic, we cant trust most people out there. I agree with the guy who you quoted, saying bioware should implement a system to record the chats, catch the ninjas, punish them, return the mats or item to the original buyer. Its not a bad idea. Its an MMO, whats the point if we cant trust and co-exist with other people? If everyone sticks to their own guildies, and no one can work and trust anyone outside their guilds, the MMO wouldn't be succesfull. Before you come bashing me back, take into account this is just my OPINION of what makes sense to me.