Not just in DAU either. Mind-share wise, it has a huge influence on the wider web and is increasingly the platform for content stealers (the 9gags, buzzfeeds, and facebook pages).
9gag has been caught time and time again using bots to just rip off whatever was trending on reddit's r/all feed (most obvious when they copy SubRedditSimulator, which is just a Markov Chain recombination of other trending posts).
This has been going on for years.