By the way the cheapest purchase URL in the UK seems to be Amazon: Amazon UK purchase URL (http://www.amazon.co.uk/exec/obidos/ASIN/1593270690/026-3870825-6886835) which is much cheaper (£23) than both the publisher and the US site you list .
But this isn't only true of software...
The productivity gap between best and worst, in my view, is as true of many white collar offices and especially true of research labs as it is in IT. It is also as often true of sales teams. But as mentioned I think the big picture is always that surviving on your own is much harder than doing your job: your job has to fit into a huge mesh of people and relationships to work. BozMo