> and it runs just fine drawing 1500W.

You think that this is "just fine" because you've never experienced the glory that is a 3kW kettle!

I get bored and tend to wander off waiting for it to boil at 3kW

1.5kW must be absolute agony

I'm pretty sure in our current rental the kitchen and laundry are on the same circuit, which means I'll often have the dryer, washing machine, kettle, toaster and microwave drawing power at the same time. It's never been an issue.

Why would regular sockets need to supply that much juice