Wix resign?

I've got a customer who's got an ok Wix site with the an ok design, doesn't suck, but it's not that high level.

I don't want to resign it as I don't have the time. Can you export a Wix site to edit it outside of its native tools?

Also could you import that back into Wix?

Why would you use Wix, over say a regualr domain? Is it just ease for non IT people?