Allow large format canvas for outdoors/billboards design without scaling
Using Illustrator (or InDesign, for that matter) to make outdoors/large printing projects is a huge pain - many times the production team (which is usually NOT the same team that designed the thing) doesn't read properly the instructions, and then errors happen.
Also, other older software packages don't suffer from that kind of artwork / artboard size limitations.
Do you ever use Flexi Design? The size of Flexi's canvas is limitless and you can take things straight into your rip program from it. You can import ai eps & pdf, almost all formats, but it doesn't convert strokes, gradients or transparencies well. You have to expand strokes and flatten transparencies or gradients to ensure there are no strange outcomes.