[archi42]

To me this still sounds a lot like "everyone buys private helicopters before affordable flying taxis are a thing".

An autonomous robot suitable for generic (or even a few select) tasks is rather complicated and/or requires non-trivial infrastructure at the site of service (e.g. grocery store).

For example a carrier bot following the delivery person is much simpler in comparison and can increase the efficiency of the mail delivery system without putting new infrastructure in place everywhere. With standardized mail slots some deliveries could even be automated (still less complex than a robot at every shop the fills up your robot or your robot having picker capabilities; plus your robot might need your car to get around).