I worked once for a company where half the calls to customar support was for ancient products. The cost of responding to these calls with "we do not support this fossil" which usually took several minutes because, invariably, "can you just answer this" or worse came up was enormous. Maybe the removal of the above is the only way to get rid of that cost.

If there was such a high demand for this kind of info, and such a cost connected with it, the wise move would be to provide all the support the customers need for the obsolete products - for a fee. A separate support line for obsolete products, say, $3/minute, seems like a great opportunity for me... You're obligated to provide support for your product during the warranty period for free, but later it's definitely your right to charge for that. This way instead of lose:lose situation (you lose time=money, customer doesn't get answers) you get a win:win situation (you profit, customers get the support.)

Anyhow I see nothing wrong morally or otherwise to do whatever you want with something you own.
That way of thinking is one of the fundamental evils in our civilisation - see the starving beggar example.
The name's greed.

If the above action bt a company offend you, stop dealing with the company and - if you need to vent - post in a forum why you did so.
, which is exactly what I'm doing :D