Nope, they have kiosks right as you walk in and you can just swipe the card you used to purchase the tickets and they will print out.
Nope, it's very convenient
No. The staff can scan your screen on your phone that will have the ticket/bar code/QR code.
Nope. You should have a QR code in the app.
No need to print as long as you can bring up the ticket/barcode on your phone for the counter attendant to scan.
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