As do many subs.
/r/Paladins - no unrelated content NN post.
/r/PCMasterRace - rule 7 states "Age, nationality, race, gender, sexuality, religion, political affiliation and economic status are all irrelevant here." NN post.
/r/NoMansSky - no off-topics NN post.
/r/videos - no politics; post in /r/PoliticalVideo ... NN post.
Shall I continue?
/r/LifeProTips - no political tips. NN post.
/r/Music - must stay on topic to music. Threads often get locked due to uncivility/politics. NN post.
/r/Gadgets - must be related to a gadget. NN post.
/r/Hearthstone - content unrelated to game is removed. NN post.
Really, I could sit here and take more time out of my day and pinpoint hundreds of subs that are "breaking" their own rules by posting something on the topic of NN.
There isn't any easy way avoiding a post, a pop-up or an advertisement for Net Neutrality today. The most a user can do, on Reddit specifically, is using the r/all filtering tool (must be logged in, applies to only your account) or download Reddit Enhancement Suite.