On Facebook, I see edit scams all the time. Someone makes a post about a missing dog or something, tons of people share it around, and later it gets edited to something trying to sell $10 sunglasses. As ridiculous a technique it may be, it hinges on people's emotions to work. Whether they sell any sunglasses or not is beside the point. Over time, the people sharing those posts become reluctant of what may be legitimate information & the actual missing dog gets no coverage.

Aside from complexity & centralization risk, there's a lot of moral reasons to avoid it, especially when delete is getting adopted. From a user standpoint, if missing context or a typo is that big of a deal: delete it, repeat it. It's not hard. #forevertypo