I used one yesterday far off airport. I got 3 due to a recent IRROPS overnight, spent one on dinner for myself that night, bought dinner for the guy next to me with my second, and still had one left over when I got home. Hit up a Chik-Fil-A on the way to the house. Did a mobile order to avoid cashier confusion and it worked like a charm. The vouchers include the credit card number, expiration, CVV, and billing zip code.
The hotel I got put up at was very familiar with the vouchers; waiter gave me a piece of paper and asked me to jot down the 4 pieces of info. I used a mobile order for the Chik-Fil-A specifically to avoid trying to explain to a teenager how to manually run a CC.
The only sucky part is that the guy whose dinner I bought didn't tip, so my generosity cost me, as I made up the difference to the waitstaff.