Yes, that's the point, it's only done half right. Sandboxes are like AAA junk food, because it lets them make a whole bunch of Literally Nothing and sell it as a game feature. Your sandbox needs to come with a number of those little plastic castle makers equal to the size of said sandbox.
I cannot think of a single developer who has ever matched this obligation, but Rockstar gives it a good shake with RDR and GTA.
Part of the issue is, much like with the Freeform Space Simulator or Zombie Apocalypse (eeeyyyy RDR) games everybody wants is that it only exists in the heads of hyped up gamers. It's almost impossible for sandbox to work out as long as marketers can put "x2km map size!" up as a feature. There's only so much dev time to burn on these things. This is why I'm terrified for Breath of the Wild, because while I think it might work out there's a high chance it won't.
Take MGSV. Good game. Great game. Has no business being a sandbox and is mostly wasted because of it.
Call of Juarez is a good counter-example actually, because while it has sections with a lot of nothing it's a constructed nothing, because it's meant to convey a sense of journey instead of going to your next fucking map marker.
That's another thing going for Yakuza, at least 3 onward (can't remember if 1 and 2 had things...) since you could spend hours just pissing about doing things not related to beating the shit out of everyone. You can play various Japanese gambling games, mahjong, shogi, do some karaoke, bowling, darts, table tennis, a fuckin' weird massage game and other things I can't remember.
In the fifth one, you can even play an entirely different video game! There is even a mandatory rhythm game section for when you want to indulge your inner pop princess
and it's super-duper fun.
The main game is solid, and you could get lost in the rest of it for feckin' days, man.
/plug
