We have several clients which show 6 sets of yardages on their scorecards (black, blue, green, white, red, gold). In many cases there are only 4 tee complexes per hole, and 2 sets of tee markers will share the same tee.
Their state golf association has established 6 different course & slope ratings: four for men (black, blue, green, & white) and three for women (white, red, & gold).
This set-up allows for variety and functional posting for handicap.