I can understand the astonishment, as indeed marketing staff has been instructed to never reveal this accounting practise. They reason why casinos do it, is that some patrons require very few comps to be satisfied, so by not showing them openly what they are entitled to, casinos can save money.

Living in a gambling city for 18 years, I know all about it. Staff knows that I know, so I openly ask them about their (marketing) system.

One simply needs to keep in mind that what is offered as for free, may not always be for free