> counter circuits were shared with the refrigerator

Ouch. Code here (Ontario) is that not only does the fridge need a separate circuit, but counter outlets need two separate circuits: each socket on the duplex outlet is required to be on a separate circuit (although multiple outlets can all share the same two circuits, but you're supposed to alternate top and bottom).

Of course, if your home is older than I am or it's a handyman special, all bets are off. If I run the microwave while someone is vacuuming in another part of the house it'll trip the breaker.