And you can gamble at the stadium including at halftime. It's the best! athletics, I've often thought of exchanging, especially when the exchange rate was creeping towards 20 to 1 but in the end I just don't worry about it and spend USD. If you eat at any of the nearby restaurants at the stadium or along Aguascalientes and in the "Gastronomic District" you can use your credit card. You might have to give a travel notice to your bank though. I haven't been to a game all year because Fridays are impossible but really hoping to go to the playoff game this weekend.
I knew I was going to be in town for two days so I exchanged $70 for $1400 pesos but also kept some cash. Pretty easy process. I have an app on my phone that displays the current exchange rate so I knew what I was doing the entire time I was spending. Credit cards are easy too. A lot of places they display pesos and USD on the receipt.