I always make it a point to tell people that I'm going to report them and for what exactly. People usually end up throwing a hissy fit and telling me "lol u mad", so I'm sure they remember why they get banned.
I don't plan on making a post for everyone that breaks a rule by accident, just the repeat offenders and people who are real cunts about it. This is not about me being butthurt or anything, however if someone is going to mess with me multiple times, I think it's safe to assume they will do it to others as well. Seeing as the majority of people don't care enough or don't know how to post demos, I've decided to start doing it myself.
For example the last guy I reported (lachonariumm) literally disrupts teammates every chance he gets and there have been numerous complaints about him. Just look at this post (link) where an admin (phil) tells a player (superman) to post a demo about him.
There are certain players that come to the ZM server to ruin the fun of other players and break the rules whenever there are no admins present. Keeping these trolls around is not a good way to increase server population, if anything it will decrease the population count because people get tired of trolls.
Also I remember reading somewhere that admins are not to trust players without any evidence (which I fully agree with BTW). Pestering admins on steam won't do much seeing as these trolls don't troll when admins are around and getting an admin warning is like foreplay to them.
I really appreciate that admins evaluate these demos and punish offenders accordingly. It really helps make the servers a better place. I'm trying to keep the reports down to a minimum, however there is still a lot of unnoticed douchebaggery that goes on when there are no admins around.