Shouldn't a kitchen 'fridge be on it's own circuit?
In the US, under the NEC, a residential kitchen fridge is not required to be on a dedicated circuit. It is certainly a good idea and best practice, but not a requirement. A fridge can be on one of the minimum two required "small appliance branch circuits". 

A 15A duplex receptacle is rated for 20A feed-thru. What you are reading about "15A only" is regarding the push-in wire connections in the back of the receptacle. They are limited to #14 solid wire and a 15A circuit. Check out the wording in the image in this related answer: Can a 20 amp circuit have a 14 gauge pigtail directly to one receptacle?

A "well-regarded" builder would never put a fridge on with the counter receptacles. Not unless this is a code-minimum tract home.

As for kitchen receptacles being shared with receptacles in a laundry area, this has not been allowed by code for many years. Well before 2000.