We don't tip the Maitre 'D either unless he does something for us like change tables to a window or seating times. But some will argue that he does other things for you which you don't recognize such as:
1) He arranges for newlyweds to be with other newlyweds
2) He arranges singles to sit together
3) He arranges families with children to be with other families
4) He is the dining room manager of the service staff and keeps them focused
5) He arranges special dietary meals for those with special needs.
6) He arranges for anniversary couples to sit at a two-top
But I think it's recognized he gets a decent salary that's why the suggested amount is $.75 per person.