It does, however, mean that any type of appliance that you might wish to plug in uses the same plug, regardless of what power level it wants - quite a good example of It Just Works, even if the price you pay is huge plugs.
Of course, that does break down a bit when you get to fuses, since you now have to worry about using different capacity fuses for appliances with different expected maximum power draw (3A for most things, 5A for the odd high-power small appliance, 13A for anything involving a heater...)
Actually, UK buildings typically contain at least three different standard sockets and plugs--the big ugly ones (with a supply of four different fuses needed), a mini version of that design commonly used for table lamps and floor lamps, and a third design allowed in bathrooms so you can plug in an electric shaver (electrical sockets and even light switches are ordinarily barred from bathrooms). There are also many different kinds of lightbulbs (screw-in, push-in, push-and-turn-to-lock-two pins) in many different physical sizes (as well as different wattages). Running a family house requires a considerable stock of bulbs and fuses, which explains all the "electrical supplies" shops which are unknown in the US. Up until about 10 years ago, in my personal experience, UK small appliances, lamps, etc. were sold with bare AC wires and the householder was expected to add the needed style of plug; now everything comes with the huge plugs.
What are these mini plugs? Everything I've ever seen has either the BFO plugs or the wee razor type plugs that go into the BFO ones with an adaptor. I've never seen a socket in a house for razor type plugs (although hotels do have them) - I guess new properties might have them.
Of course, that does break down a bit when you get to fuses, since you now have to worry about using different capacity fuses for appliances with different expected maximum power draw (3A for most things, 5A for the odd high-power small appliance, 13A for anything involving a heater...)