I have recently designed a food product bag design to be printed on a 3 seal laminated foil bag. I produced graphics for the design in Illustrator, retouched product photography in Photoshop and laid everything out in InDesign. The print shop apparently does not use InDesign. Is that industry norm??? I am need to sending something like this to a press, but am finding it hard to believe that the only way to send the file would be as an .ai. Am I crazy?
A print shop requires and requests the highest resolution artwork possible.
An illustrator file is usually the best bet as far as resolution goes because of the vector based artwork.
You could recreate your layout using Illustrator and send this off to the printer.
Alternatively, ask the print shop if they will take a "Press Quality PDF" you could, depending on your artwork, create a Press Quality PDF using InDesign's export tool and selecting Press Quality. (The printer may also request bleed and trim marks.) Please see:
Make sure all of your artwork is at least 300dpi or a vector based EPS
Note: Potentially the print shop can supply a template/specs that you could use for layout in illustrator.