stand to a treat
stand (someone) to a treat
To pay for someone to do or receive something enjoyable; to treat someone (to something). If you don't have any money for ice cream, I'll stand you to a treat—it's not a problem.
Farlex Dictionary of Idioms. © 2022 Farlex, Inc, all rights reserved.
stand someone to a treat
to pay for a treat for someone. Come on. Let's go out and eat. I'll stand you to a treat. It seems as if I am always standing someone to a treat.
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs. © 2002 by The McGraw-Hill Companies, Inc.