Yeah...been to Bermuda 3 times (soon to be 4X). I have never seen drug sniffing dogs (or sniffing for anything) on any of the cruise ships I've sailed (~20).
If someone reports it, the cruise lines' security will investigate.
As far as dogs going up and down the hallways, not something I've seen.
And, unless the cabin steward sees the edibles, and is certain they are cannabis edibles, I doubt a drug sniffing "anything" can identify it.
Does that make it "OK" bring illegal substances on the ship? Absolutely not!
You agree to the Ts and Cs on your ticket. If you disagree with them, white to the crime line and log your complaint. But, if you're rolling them and smoking them, after all the warnings, excuses should fall on deaf ears.
Pay your fine, or worse, as a lot of foreign countries have stricter drug laws, you do jail time. If that's not enough of a deterrent, the U.S. Consulate is NOT going to bail you out (even if you're offered bail by the courts).
Pretty big risk just for a "high" or not looking for other means to deal with whatever ailment you use it for.