That particular sub-reddit is a mixture of real people, and trolls who pose as trump supporters to egg the supporters on, as well as scaring and pissing off people against trump. The result being that with little effort and prodding on their side they get to see glorious internet mudfights.
However due to the way they're doing it, it's hard to tell which is which. That puts reddit admins in a bind and they have to balance things. Do they keep distance and let subtle trolls go unscathed? Do they take harsher measures and hit actual trump supporters? How much of this spills over into other reddits? How to handle the /all pollution? Letting it get in there just increases the mudfights, but if they take steps they'll be accused of censorships.