Let’s say I decide to go to a nice restaurant for a meal. The dish comes out, and I ask for a salt shaker before I even taste it (I never have, btw). That is normally considered an insult to the chef or you are pegged as a neanderthal diner.
Why, then, is it normal for a waiter to offer you grinds of pepper all over your plate before you have even had your first bite?
Pepper is best when fresh, and its an easy way for them to provide an experience for diners where they feel like someone is giving them special care when it comes to their food, if that makes sense. Salt makes no difference freshly ground. Also, at least in the USA, generally no one will be insulted if you ask for salt; is that an experience you have often? And do you have to ask for salt often? Anywhere I eat they just have salt shakers available, it seems odd to me that they’d make people ask