I'd like to either force App Store to save my password, or have it automatically entered (just for the Mac App Store password prompt) when it asks for my password. I want this because "require after 15 minutes" is far too limiting, since it's a pain to get my password. How can I force App Store to extend the duration of saving to indefinite, despite that it's designed to save the password for 15 minutes?
Note that I know this isn't the case for free apps. I want to purchase apps without having to enter my password. Is there a way to do this?