Certain Database (Depending on Country) requires verification via Finger Prints as they may not have all digital records of entry/exit at port - When you get flagged at in airport for travel, they do a background check of the individual from all possible database - this is a very similar check, just that for IRCC takes a longer processing time.Why would they ask for fingerprint ? I mean I submitted application for my family of 4 and I don't think I submitted any fingerprint.