You're agreeing with me. Psychologically, once you have a potential buyer in your physical presence (especially outside of their environment), you have a tremendous advantage in closing.

And sales where you're giving a sample like whisky? The social obligation to reciprocate for receiving something "free" is very strong. The idea behind giving a sample in a sales pitch isn't to get them to like the whisky (though it helps eliminate/reduce resistance), it's to incur that social obligation.