These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
Memetic Mutation: The strips detailing the precise use of the apostrophe and comma.
Moral Event Horizon: Bob putting down a dog with a shotgun, according to the creator's mailbag, which forced a change of publisher. Ghastly acts of genocide didn't even rate and neither did a strip with an Anthropomorphic Personification of America murdering Jesus. Naturally enough the next collection was entitled "Dog Killer".
Seasonal Rot: The strip has declined in quality over the years, probably beginning around the time the author also took a job at Popcap Games and had his creative attention divided. Notably, a tagline at the title screen of Minecraft is "BTAF used to be good!"
The Woobie: Freddie is a frequent, usually undeserving, target of Bob's rage.