When a mod removes a comment, the user still has the ability to make edits to that comment. This hurts the mod when the user takes a screenshot of the edited comment to make it look like the mod abused his powers when the mod removed it.
with how simple it is for someone to modify the dom in current browsers, do you think this would really stop anything? if someone wants to make it look like they said something else, there are many easy ways to do this. at least when they edit through reddit, it shows the asterisk indicating it's been modified.
Yes. Because at least this way, I (as a mod) can do a counter screenshot with the real comment that any other mod could back up. Allowing them to scrub all evidence from the real comment puts the burden on the moderator to screenshot every comment they remove to retain the evidence. Not to mention, I have seen moderators reverse other mods' decisions because the comment has been altered to make it seem like the moderator abused their power.
I could go on more about why this is needed but I think it's pretty clear.
good points, hadn't thought about that
Thanks for forcing me to expand on it. :-) You made me realize that I didn't really give all of the reasons I should have in my original post.