Yes, but not in Canada. Many years back, tried a full-day at an exotic spa in Mexico. It offered a day rate for unlimited food, drinks, hottub, sauna, massages, 18+ activites etc. I found the quality of the girls disappointing. Despite the AYCE nature, I did not find that I got my money's worth. Also did a half day in Bangkok where the operator arranged for a full service massage to end the session. I concluded that the massage with extra was the only part I truly enjoy so I haven't been to a day spa since.
Also, if you do business in China, taking a customer to a bathhouse (basically a spa for men with all of the amenities) is not uncommon. Some of these bathhouses are huge, like 4 or 5 floors. All big bathhouses have private rooms on a different floor away from the public. Paying for your customer to go "upstairs" is not an uncommon practice. A lot of things can happen in those rooms and the cost is simply charged to your host's account. It is not cheap, if you are paying for yourself, make sure you get the menu with prices on it; they have different versions.
With today's prices, it may be cheaper for you to buy a plane ticket to Mexico, enjoy a spa day then fly back than to try to arrange something locally.