My mom lives in Florida (land of the snowbirds). Her friends are less likely to buy round trip tickets. They often buy one-way because they are unsure of their return date, or perhaps they will drive a car back north, etc. As such, this increases their likelihood. In addition, many are naive to frequent flyer programs, or fly tickets on different carriers. Both of these factors play into SSSS. Add expired IDs, metal replacements, and less familiarity, and you have the very sad scene of these folks being groped for this foolishness.