You'd be surprised... (Destiny)

by Xenos , Shores of Time, Friday, July 24, 2015, 17:30 (3647 days ago) @ Korny

Made a trade in Warframe once with a kid. I offered him a great deal for a super-expensive item, then casually tricked him into screwing himself over (he paid up front for the entire trade, while I initially gave him the cheap components of the trade). It was ridiculously easy, and I only did that to see if he actually would fall for it. Of course, I kept my word and gave him the expensive part because I'm not that evil, but he blindly trusted me. Didn't even stop to question the logic of the deal because I was real friendly and casual.

Now imagine doing that online. Join an LFG group (mostly kids on XBL in my experience), help them out, then offer one of them a wonderful deal ($10 for three nightfalls with my friend! Nine chances at exotics!). Heck, it doesn't even have to be kids. I've had adults in Warframe pay me Platinum to ferry them through missions. If you add a trade economy, it's ridiculously easy to exploit. I say that because I've seen that happen.

And once again, I get it, it WOULD happen some. But even in your example, you are promising a specific, super expensive item, not saying "Hey give me money and I'll help you get 9 random drops." There is a difference in magnitude there. While the after round trading could introduce SOME exploitation, it wouldn't be to the same degree as a normal trading system does in an MMO.