A Bloody Mary is breakfast. It is a meal replacement. This is why you add celery and olives.
Some people use V8 rather than clamato or regular tomato juice.
To me a Bloody Mary is something you drink in the morning on a cruise ship, or in a bingo parlor in a casino in the morning, or at brunch. It's sort of a non-guilty morning drink like a mimosa. It's a drink and a meal so you don't feel like you're drinking hard first thing in the morning. It's also sort of like a hair of the dog to take the edge off after a night when you've been drinking a lot.