I feel it is perfectly reasonable for a vendor to communicate the lifecycle of their software. Lets face it Microsoft give ample warning and a long period of time when their software will be supported, enter extended support and then have withdrawn support. Case in point Active Directory 2003 which went out of support in February 2015.

If I was running a small company I would worry about the overhead of supporting aging versions of my software. I simply wouldn't have the manpower. Perhaps I would offer customers discounts and incentives to upgrade however the discount game is very dangerous for small players where margins are tight.

One horror story I was told was where a company had been paying for critical support only to have an incident which required that support to be enacted. It became horribly apparent that the support provider had gambled on the stability and maturity of the system and had not retained the skills to meet their contractual obligations.