You really don't care as much when its got mains power but not all of these devices are plugged in. You will see them a lot in simple hand held consumer electronics like garage door openers, remote controllers, wireless mouses, kitchen timers and so on. In battery powered devices saving a mA make a world of difference.

mA may matter for something like a phone but really the war in the 8bit space is over uA and nA.

Many 8bit mcus end in places where their battery is expected to have a life time measured in years. Last I looked I think MicroChip is leading the way here in terms of sleep power. Their PIC XLP series only draws ~20nA while sleeping.

There is more competition in the 16bit space with the MSP430 from TI.

You seem to be missing that it is always a good idea to save power.