Yes, that's true. I suppose I always think the same. I've never facebooked anyone's number before though to have my thoughts confirmed. To be fair to him he didn't know who he was going to meet either first time. But if they're going to do this sort of thing and don't want us snooping get another number so they can't be traced. Or don't have the number they are using on social media 
I am constantly amazed by how careless guys are, i.e. giving me their real full names without my asking and I would say the majority use their personal phone too!
Ah and to get back on track I find guys who are almost silent during a,booking unnerving and those who stare at you constantly or compliment you non stop.