Thanks for sharing :) For one, most of the time we don't use support on themes, rather, we help troubleshoot the error when there is a conflict.

But yes, will check out ThemeFurnace :) Though some theme shops are saying it's unsustainable, look at how StudioPress is doing. And even ElegantThemes has decided to go on board with lifetime licenses. There's a fine balance between a well made theme (which sells well, and needs less support) and one which has tons of short codes on the home page, just because they want to be everything to everyone.

Finally, subscription based theme shops are ok, if the prices are reasonable. However, those going at a few hundred and 50% renewal make it hard for small time users like us. And it prices Wordpress out of the hands of the masses. Why not go for WiX or Shopify then, when we can get our hosting covered as well?

I think there must be a balance between prices and renewal/subscription. Look at Magento's extension. Some can be up to a few hundred bucks, with 90 days renewals. On the other hand, Open Cart's extensions for the same feature can be as low as 20 bucks :)