That argument only makes sense if people don't really understand what a VPN is or what it is actually for. They're somewhat of an expensive and complex thing that usually noticeably slows down your internet connection... I doubt many people are buying them because they think it protects them from identity theft or something. I haven't seen an ad on the internet in a decade (thanks uBlock) - so I'm not sure if there's some ubiquitous misleading ads I'm missing.