Nhathanh, I think the bellboys will just get loonies and toonies, which means the day that Canadians leave, they will have many bellboys with a handful of coins asking to exchange for a Canadian five or ten; they can then take the paper money to the bank, as the banks do not exchange CUC for Cdn coins.
Of course, this goes counter to all the discussions we have had over the years about NOT TIPPING IN CANADIAN COINS!!! Oh, the irony!
I usually carry a few tipping items (yes, I’m one of those people!) in my carry-on - and have tipped with baseballs, stainless mugs, or small cutting knives on different occasions. I have in the past brought down 20 extra kg with humanitarian allowances for medications with the airline and so the poor bellboy has earned his tip!