Amps x Volts = Watts... so what?

Once again I've that feeling that I'm missing something.  If you have an electrical appliance that performs a task then it will take a specific amount of electricity to achieve that.  A more powerful appliance will do the job quicker, and a less powerful one will take longer but the amount of electricity used will stay the same. So what is the point in the EU's latest regulation restricting the size of motor allowed in vacuum cleaners?  And it appears that this sort of restriction will in due course apply to hairdryers, toasters, kettles and such.  As far as I can see, all it means is it will take longer to vacuum your house, dry your hair, make your toast and boil your kettle but the power consumption will remain the same.  Where's the sense in that?