They could do good work.
The general rule of thumb is that the internet is 10% useful, 90% photos of pussies and kittens.
Given that the halfwits who believe that the internet would magically have a video of the royal clunge disgorging another screaming mess of selective inbreeding are almost certainly the same idiots who think that by Liking a photo on Facebook then some huge socially important change will magically happen.
Therefore they are guaranteed to be ones causing all the global warming by requiring the Internet to have the bandwidth needed to store all the cute kitteh photos and faux-social-commentary-like-this-now-to-ensure-the-Alsatian-puppies-get-their-cancer-treatment-police-justice things.
Thus, the malware can be used to identify people who really shouldn't be allowed an Internet connection. Which would negate the need for Kittehs, meaning about half the Internet would suddenly be freed up.
It is likely this would cause job losses at hosting firms, and limit the growth of security software houses.
It is also likely the security agency snooping on web traffic become more effective, as they'd no longer have to wade through endless videos of cats doing cat things.