For myself, if I pay for an app I expect a lot more from that app. I expect a quality apps with updates and support. There was an article I read (can't find it now) that a developer said he doesn't do payware due to the fact that he doesn't want to give support.
I have no problems with free apps ceasing development - they were free! It would be nice if they released the source code though so someone else could take charge of the app.