From the FAQs:
What is this site all about?
This site is all about Canadian money, and where across the country the money has been. When you enter in a note, the system saves all the information in our database. Then, if someone else comes along and enters that same note, a hit occurs and you will be able to see who else has had that particular note and even better, where the heck the note has been.

False entries diminish the enjoyment of all those who agree with the above statement. Any hits on those entries do not truly reflect the movement of banknotes. And for us closet statisticians, it also skews the data that has been collected to date.