LOL - I've never heard of such a thing. You have my permission to tell him I said no proper lady would date a man who puts salt in his beer. You can use me for an excuse.
We used to put salt peanuts in our RC Colas when I was a kid. I'm not exactly sure why, but that was the style. ;0)
Okie-doke, sounds like I now have my best, most “legitimate” excuse...lol