Even if you aren't reading the instructions, isn't it still better to use it than not at all? At least you're getting SOME of the little buggers. Some is better than none in my opinion.
Same could be said about people's hands. Some people either don't wash their hands or only use alcohol-based sanitizers. Really, you should be washing your hands for at least 10-20 seconds in hot water with firm friction and THEN use hand sanitizer on top...but really, at least washing with soap in cold water is better than not at all. Alright. Getting off my soapbox now.