I see what they are trying to do. The old cartoon network used to do this all the time. In fact, the whole concept of the channel revolved all the characters living in one Universe. That is why you saw a lot of cross-overs in the old times. I remember when the announcer used to come on in the credits at the end of a show and say how he/she was walking down the street and came across people from cartoons and then she would announce the next show.
It doesn't work now-a-days
