Nowhere near as commonly as other fish, though (at least in most regions). In my circle of acquaintances very few are even willing to try octopus or squid, and I don't know anyone who eats cuttlefish. I live in the Midwest US, though. If I lived in Japan, I'm sure that'd be very different.

I'll grant that other fish are eaten more, but cephalopods are commercially fished as well.

And for anecdotes, I live in the Midwest US and had cuttlefish last week.

And I eat octopus on a semi-regular basis (and squid when I can convince people to get a Calamari appetizer), but it's not suuuper common here, unless they're big fans of sushi.

Those people do exist in the area, or the restaurants wouldn't bother to have them on the menu, it's just uncommon.

Not all, many species of cephalopods are unedible in fact.