Firstly, WavePad does not automatically launch RecordPad, it is likely you installed this application yourself during the "Select Related Programs" stage of the WavePad installation. You are able to fully uninstall/remove any of our software products by using the Windows Add or Remove Programs window which is available from the Windows Control Panel.
Secondly, the Purchase Software page for RecordPad specifically states "RecordPad Professional Licence", and even offers a link back to the products webpage to allow you to double check what you are purchasing. No where does it state that you are purchasing "WavePad Sound Editor Master's Edition" (except in the bundles). I'm sorry that you didn't take the time to check your purchase before blindly giving away your information.
Also you say "They don't even ask me for my mailing address" but you then go onto "The next page indicated that if I had purchased the program and wanted it mailed to me, I would have to email them ... with my mailing address". Can you please clarify your troubles?
If we didn't remind customers that their trial version was about to expire, and then all of a sudden their software suddenly stopped working, how do you think they would react then? Don't you think they would have asked to be given some notification that this was about to happen? Unfortunately both sides can't win.