A Mets stadium vendor used his beer tray to try and catch a foul ball, and it almost worked

Anything can be a glove. Anything.
If you don't happen to have a mitt with you at the ballpark -- which is a hot-button issue in some circles -- you have to get creative if a foul ball is headed your way. You could grab the ball with your bare hand (while holding a baby), perhaps.
Or, as a Citi Field beer vendor attempted in the Mets' 6-3 win over the Padres on Tuesday night, you could attempt to use your big plastic tray of ballpark fare as a makeshift glove:

It didn't quite work, as the baseball bounced right out of the tray like that impossible carnival game with the softball and the basket -- but the ball did end up in the hands of an excited young fan anyway.
We'll call that a success.