-Both girls work in a store in the shopping district
-Both girls are optimistic and happy
-In both stories there's a guy that likes them but can't muster up the nerve to say so
Soredmo Machi the form a band and in Tamako market they cheer with batons.
Both girls also seem drawn to interesting and troublesome events.
Both really cute stories
They are similar in that both anime use the shoutengai as a major setting and comedic.
Both also involve some slice of life and super natural elements, the general happy-go-lucky non-sense, and, more or less, self contained episodes.
Both are great comedies that rely on rather random stories to provide humor. Characters drive both shows with magnificent displays of stupidity at the most unfortunate times. If you feel like getting away from all the overly perverted jokes that are now saturating the air waves, check these out.
Two comedy animes that can be referred to slice of life genres, both animes happen mostly in the cafes their working... Both animes seem to get their punch lines mostly on the worker's "unusual" sides too... If you like that format of comedy of Working, then you might also have fun watching Soredemo...
The style, humor and atmosphere feel the same in both series the main difference is that the focus in Zetsubou Sensei is set on the teacher and his students and in Soredemo Machi wa Mawatteiru it's set on a group of students and their daily lives.
If you have watched Gintama, you would have realized the story is about more than the three main character: it is about the town of Kabukichou. No character in Kabukichou is insignificant. Soredeom Machi wa Mawatteiru remind me of Gintama, specifically the communal aspects that were made possible by bringing together different unique perspectives from the residents, be it: fisherman, cop, vegetable seller.
Both are slice-of-life comedies about a group of moe girls working in a cafe (or a dessert house).
Supernatural element is contained in both series, but it is not such an important component in Gochuumon as that in Soredemo.
Gochuumon offers a service for yuri lovers as there are no young boys in the main character list. Gochuumon has a romantic storyline between boys and girls but you can also imagine Shoujo Ai of Futaba×Hotori.
Humor are the same. Animation style is also identical. We are also dealing with the same airhead MC girl. While Arakawa is the more unique and downright weird, the comedy factor and style of story telling is the same.
Also, both anime are very fun to watch. After your done watching Soredemo Machi wa Mawatteiru, go to Arakawa Under the Bridge right away.
While, at surface level, neither show seems all that similar, they both adhere to very surrealist senses of humor. This humor eventually all culminates into two finales that push surrealism as extreme as either respective series can go. They also make use of more out there, fantastical elements in an otherwise grounded, everyday setting.
High school students mucking around is the general premise of both series'. Neither are parody or non sequitur heavy. The laughs generally come from the main characters' crazy machinations and odd behavior. Both series' also feature amusing student/teacher clashes.
Both have very similar pacing and humour style. Although they don't look similar at first, they both have pretty much identical mood and atmosphere. Their main dish isn't comedy or outrageous random laughter, but about life and daily routines of interesting characters.