my bachelor's was in hospitality and in my revenue management class; i distinctly remember our professor warning us of giving frequent business travellers a lower rate without them asking for it...

"if you have a guest that stays with you quite frequently for business, and you have a special rate for frequent visitors; do not give him this rate until he/she asks for it, as they will be upset that they will lose their airline miles"

he was very absolute about this i remember