Re: Makes you think....
@Lee D - I don't think you understand the point of music charts. They are not to list the most popular songs ever, or which songs people are actually listening to. The latter being impossible to measure across the industry, only for individual, online services. The only thing that can reasonably be measured across the entire industry is what is being bought. Old songs/albums that get re-released can and do get charted.
Of course it is used for marketing. People are notorious for staying safe and doing things that are popular rather than taking a risk and forming their own opinion and it feeds directly into that.
But it has benefits for the consumer as well. People who are into keeping up with modern music, and why else would you listen to radio/streams that play chart music, get a continually updated list of what is popular currently. Going by sales is arguably better than any generic algorithm for measuring what is popular. When my mother tells me she wants to new CD by artist X for xmas I don't go and look them up alphabetically and try to guess which of 10 albums might be the newest one. I go to the chart corner and get the one I find there by that artist and know there is a huge probability that I have the right one.
The same goes for any chart of any genre and/or commodity. It is a tool to show similar, recent things in a given category, not a recommendation.