It's even simpler than that - false accusations often happen. Especially when the invitee has an ideological axe to grind, as so many do with any conservative politician.
This is personal self defense on more than one level - something only a Liberal, a raging feminist, or a fool (but, I repeat myself) imagines it unnecessary in today's climate of political accusations and/or blackmail.
Well, perhaps it is for them.
But normal people know what traps are often set out there to snare the unwary into a sexual harassment or similar lawsuit or compromising situation. This is how Feminists and Liberals so often prosper against their political and personal enemies.
You are exactly right. There may be many reasons for a man to decide to conduct himself this way, but when you see all the false accusations and character assassinations that public figures are put through, it only makes sense for a man in an important position to protect himself in this way for practical purposes.
Given the world we’re living in, to NOT do so would be a sign of poor judgment and of a lack of wisdom.