By not supporting old browsers with all of their inconsistencies, a team can save a significant amount of development time. That development time can then go directly towards new features, bug fixes, etc. It's not so much that the latest browsers can do so many new things (though in some cases it's that as well), it's that you can actually develop for them efficiently without diving into a rabbit hole of IE compatibility issues every time you add a feature to the site.
Of course, it is easier to support only 1 mature platform , 1 database, 1 application server, 1 library of whatever. However we don't have this luxury even on the backend, and you cannot seriously expect it to be different for browsers.
And if you don't develop cross-platform because of lack of time this is fine. Please, don't cover it with insults about dumb CEOs and ignorant lame users - bad excuse for bad programming habits (not personal, just generalisation).
Again, there is no technical reason not to give workable version of the website to all major browser users. It doesn't have to be a pixel-perfect copy. It just has to work.
I'm not asking to support one platform or one browser or one anything. I'm asking to support the standards. Industries have standards for a reason.
I didn't insult anyone, CEOs or users, so your generalization is a very poor one.
The technical reason for not giving a workable version to IE6 is that it can take as long to make a workable version for IE6 as for all other browsers combined. IE8 is not that bad, but it's similar in principle. If I have to spend 50% of my time on 10% of my users, I'm better off doing twice as much for the other 90%.
