Even a physical 1:1 map can have utility, since it ostensibly has more portability. That is, as long as it's a map and not a 3d model. Even then, though, a 3d model can have uses, such as tailoring when the customer cannot physically be there. That is, as long as it's a 3d model and not a clone. Then again, a clone has their uses...

Whoever came up with that saying just wasn't very imaginative.

Physical 1:1 maps are still useful. They have numerous military applications, and in general allow you to become familiar with an area without having to physically be in that area, if being there or getting there is difficult for any reason.