Were there other uses? Yes.

Were they common? Well, just look at the GameBoy pocket. At the time it was designed (it released 7 years after the original GameBoy) there were a lot of people at Nintendo who wanted to get rid of the port entirely because it was barely ever used. They ended up compromising by using a different, smaller, cheaper port that needed an adapter to work with the regular ones.

Which was kind of a pain for some people because the GB Pocket and Pokemon both came out in Japan in 1996 lol.