Didn't agree with your view many years ago 2old, but I think that there is now becoming such a huge disparity, not only between the highes and the lowest, but now between the low and high in the huge middle income area. This is becoming more and more evident in the prices being achieved for housing. In my area, a one bedroom house is now circa £100,000, ridiculous, particularly bearing in mind that a single fireman, with a £10,000 saved deposit, would still struggle to buy. This of course goes further than Firemen, Nurses etc, the average working man will soon not be able to afford property, even with a second income from a spouse.
The average salary in certain areas is being hugely inflated by a relatively small percentage of disproportionately high earning occupations, I would guess that the average is worked out on a mean basis, rather than modal, which would give a far more accurate idea.