Robots who could replace some manual labour work within a specified area (say: factories), don't need to rely on batteries. We could attach them with a huge wire and plug it into power supply.
In those specified areas it's also much simpler and more efficient to change the process itself.
Automated warehouses for example don't use legged robots that climb ladders, operate forklifts, and carry boxes around.
Interestingly, the bits of manual labour still required in these areas (e.g. factories) are cheap in terms of manual labour and not doable with the same level of efficiency with even the most sophisticated robots, let alone bipedal ones (you'd change the factory to accommodate to the simplest possible robot design, not vice versa).
