The other way round on the sidecar issue are some of the later British double-adult 'chairs', like the Busmar Astral below, which except for width are the size of a teardrop (and a quarter the weight)

The bike is the family sidecar owner's favourite, the single-cylinder 500 or 600 cc Panther. Monstrous torque at idle which was about maximum revs too!
This was about the end of the days (1960s?) when a British working man wouldn't ever think to be rich enough to get even a used car and the sidecar combination was the affordable family transport.