Should a compliment slip really say 'With Compliments'?

Perhaps this is a stupid question to some, but it always bugs me. When I design new stationery for a client I always wonder whether the ‘With Compliments’ part of a compliment slip is a bit of a gimmick? Or whether it is even relevant these days? In college, my tutor always said it was a gimmick, but when I did some stationery for a client a while a go and they saw that the compliment slip didn’t say ‘with compliments’ they were confused and asked why I didn’t add this? Would you say it is a design gimmick or is it a necessity to you and why?