They are cute. They are friends. They represent innocence in childhood.
They are owned by American Greetings so they have the rights...and the lawyers to make sure the Gang and their fans stay on the well-behaved side.
They represent getting along as in staying friends and maintaining a civil respect for each other even if they have a disagreement. They may agree on the same things at times when it comes to moral dilemmas like obeying the law, helping someone, and saving things from destruction even if they may have different ways of thinking about things. They may make mistakes at times or let their ego get in the way of common sense at times...but they get along.
I wonder if haters of the Gang know how to interact with people enough to get along in the first place...or are able to draw more than one character in a drawing who actually are interacting to creatively stay faithful within the Gang story concept?
What more to like...beyond the furry kid exterior?