There's that, but even aside from 'pretend to,' depending on a particular type of gathering, if many others around you are married, you're sort of an odd one out. Making you, and depending on the culture, others around you uncomfortable. Having a paid companion gives you someone yo interact with during the portions of the event that couples interact while being present for those other larger group (or business) parts. That's how I understand it anyway. Seems more of value in more collective cultures, which is where we seem to see it more often.