Ah, no, swearing is allowed as long as it’s vulgarity, profanity is what requires an NSFW tag. It’s a very important distinction that the Reddit ToS accidentally makes.
So, in conclusion: Fuck -> No NSFW tag. Hell -> Yes NSFW tag.
I mean, they can but it takes time to do that and until they do /r/pics is adhering to the letter of the law (or at least an interpretation of it) while spitting in the face of the spirit of the law.
[REPOST] Reddit's API protest just got even more NSFW (mashable.com)