The appeal is to replace workers by using a generic platform, that when mass produced, costs less and don't require retooling. One human commodity for a mechanical one.
why do they need to _look_ human though? two legs, torso, head, two arms, does a robot need that. Why not just a giant arm (or five whatever) that can roll around?
Evolution's optimisation pressure on the humanoid shape has already done a lot of that work for us. Certain instruments like the hand and thumb are very thoroughly refined in humans. On top of that, most interfaces in the world are already designed for humans, so by making a humanoid robot you guarantee it can operate in a superset of environments that a human can.
They explicitly want robots that can replace what humans currently do, in existing human workstations, etc. You don't have to redesign a tractor for a humanoid bot. This is a kind of skeuomorphism but more functional than ornamental.
There is a lot of machinery that is designed to be operated by humans using their arms and legs, a lot of processes built around it. The appeal of humanoid robots is in the idea that all this stuff wouldn't need to change. Whether or not this is possible remains to be seen