In some buildings, I've noticed circuit breakers in what appear to be ordinary electrical boxes. For example, in some musical practice rooms, the light, fan, and a receptacle are all switched by a breaker which is mounted in a way similar to a light switch, except for a placard explaining how to reset the breaker if it trips. I would expect things were done this way so that someone who accidentally overloads the breaker would be able to reset it without having to find a custodian with a key to the main electrical box.
While I doubt that I'm going to rewire my kitchen any time soon, it is sometimes a nuisance having to go to the basement to reset a kitchen breaker if two high-draw appliances get used simultaneously on the wrong receptacles. It would seem nicer as a design to have a master 40A feed to the kitchen and then have a 20A breaker near each receptacle so that any combination of receptacles could be used to draw up to 40A total, rather than to have to worry about which receptacles could be used together and then have to visit the basement in case of a mistake. Would such a design satisfy code requirements (I would think having enough outlets total, driven through enough 20A breakers, and fed with at least 40A of capacity, should qualify)? Would there be any problems with such a design?
Alternatively, are there any outlet assemblies with built-in breakers that would be approved for permanent installation (unlike e.g. power strips), and which could be safely fed from a greater-than-20A circuit?