I don't know why some hamsters bar chew. It's always worth checking their teeth aren't overgrown. Some seem to just fall into the habit, though
, and it can lead to nasty accidents.
My Magic is a bar chewer, but he seemed best in a big rat cage with lots of distractions. He still liked to chew, but would perch in a corner hammock and chew on wooden dolly pegs I hung on the bars. Unfortunately, as he got older I worried that he'd fall so transferred him to a Rody Rabbit - very similar to the ZZ2. He chews the top bars through the mesh
Some very determined chewers will chew their way through the bottom of a ZZ2! I do like it as a cage (Dinah is in one), but I tend to find hamsters are more sociable in a barred cage. They are also more flexible for stacking etc, especially if you get one with a side door. It's harder for them to chew on bars that are 7mm apart, but not impossible.
Another option is a big aquarium or vivarium (a large Exo Terra would be my preference).
If it were me, I think I'd try a really big barred cage with lots of wood to chew and things to climb or play on, but might be best to get it secondhand so you are not too out of pocket if you need in the end to switch to a plastic or glass tank.