I found an XP PC the other day with something like 150MB worth of Acrobat reader installer files inside the following folder
C:\Documents and Settings\Shop\Local Settings\Application Data\Adobe\Updater5\Install\AdobeUpdater
How about an option to remove these use-once and store .msi installer packages. Having these files accumulating and lingering on a system for months or even years is no different to having any other proprietary junk on a system.
Mike P