[SamBam]

It's fairly well-known that some accounts "karma farm" by posting comment designed to be upvoted, and then use the credibility to sell themselves to marketers. Also, I believe it's fairly straightforward to buy votes in your posts from sock puppet farms.

Here's an old post from a security researcher that wrote papers on this topic, and also experimented with buying votes:

https://www.reddit.com/r/netsec/comments/38wl43/we_used_sock...

I am unsure what the current field is like.

[giancarlostoro]

If you moderate large enough subs you see this just often enough. They'll find another sub to farm karma on, then come to yours to spam their random new domain. I wish reddit automod could check the age of the domain since it was registered, could help, although it could also be straining on reddits part, but I've seen some weirdo who gets a new domain and spams blogspam thats just ripped off articles with ads all over. I'm surprised they're turning a profit wasting money on so many domains.

Before ever being a submod anywhere, I had no idea of half of what goes on in reddit.