Sorry I can't resist...
If you're going for accuracy, does 24x365 mean you close one day this year? Or should you actually be saying 24x365.25, or even more accurately 24x365.2425 (but still not exact).
Oh wait, we missed the leap seconds in there, which there isn't any real way to average out since they occur at semi-random intervals. So I don't know what we should adjust the 24 to...
I just look at 24x7x365 as shorthand for "24 hours a day, 7 days a week, 365 days a year", which is a common saying meaning always open. It isn't a mathematical formula. It doesn't have to be exact or make mathematical sense.
There are lots of things that if you think about too hard they don't make sense. The one this week I thought about was "hunger benefit". Does that mean we're raising money to increase hunger? One could go on and on trying to correct logical inconsistencies in our use of language. It's fun on occasion to point them out, but saying that something has to be corrected just because it doesn't make logical or mathematical sense just seems as sill as some of the phrases that we laugh about being logically inconsistent.