Another strawman. People using pirated OS's and being technically unsophisticated to the degree of being satisfied with what IE6 has to offer are extremely unlikely to buy your service or to provide any significant value to your advertisers. Basically they are leeches that will use whatever is cheapest/most convenient to them. Thus not having them as your user will only spare you some resources.
But if they really want to use your service - they will upgrade in a heartbeat (upgrading or changing a browser is no significant undertaking nowadays). If they are using your service via Cybercafes - they will get the proprietors to install another browser.
Your argument merely tells me that you either haven't developed or seriously thought about developing a service for Chinese market.
People in those areas using IE6 do pay for services. I know. We were debating this very question, and decided to look at our paid users browser choices, and IE6 was, while not the majority, not the least of our concerns, either. Furthermore, the net loss of loosing IE6 users would have been the salary of a number of people.
Finally, we can support IE6 without losing out on the benefits of newer browsers.
Arguing for or against IE6 using made up fanciful arguments (people using IE6 aren't going to buy your product) is silly. Look at your own numbers. If your first suggestion isn't that, you're ignorant of the realities of web development.
But if they really want to use your service - they will upgrade in a heartbeat (upgrading or changing a browser is no significant undertaking nowadays). If they are using your service via Cybercafes - they will get the proprietors to install another browser.
Your argument merely tells me that you either haven't developed or seriously thought about developing a service for Chinese market.