I am not one of those who say NO, NEVER EVER etc. all the time and never change their mind.
Reputation system might work in case of "support forums". This will let you see who is really helpful and trustworthy, but even is this case, such system will be abused ... just because >.< I saw that many times, even on a forum of which I was dev/tech-admin. That gave me lesson good enough, but I would still accept such systems where this might work (more or less).
Now gg.deals/community and reputation system - is there any point in adding one? Yes there is But it is neither of those discussed above:
Reputation won't chase off bots, they will do their job and that's all.That's the best case scenario. Worst one - bots will start "reping" themselves ... same for trolls and spammers. Who cares about the fact, that this or that user has -100 rep, when he can still post garbage? Rep system in such case is a reward to such user, while proper reward should be perma-ban.
As to valid reasons for rep-system to be implemented, this one is the closest to what I have in mind:
Awiaton I mean they could add reviews (new stores or games)
We're talking about deals here right? If this site will be known worldwide it will happen, that people will start posting good deals available in locally known stores. Known locally, but can a user from other side of the globe trust such offer? Here reputation system might help. But actually why a reputation system for giving points to users and not to the stores? This might be interesting - a place to add such web-stores and giving them user-reputation. Yes, that one might (and if service will get really popular - will) be abused as well But still, this is the only valid usage for reputation system I see as of now for this community.
If by any chance, this service as a whole, would grow enough to give us some inside trading system, then this is where a rep system is very much needed, but it has to be separate from the community/forum as the fact that someone can write well on forums does not mean that it's a trustworthy user, when money talks.