I can totally understand why vendors want to put a support package in place. However, I feel it leaves a a nasty taste in the mouth if you are paying for support on a theme you've bought BEFORE they introduced this policy. If I buy a new theme from this point on and know I have to pay for support after six months that's acceptable.

There are of course situations where themes/downloads have been "removed either by staff or the author". What happens under those circumstances? If a theme vanishes a week after I've bought support will I get a refund? I've bought 20 themes from Theme Forest over the years and six of those are now no longer available.