I unintentionally stole something this weekend.

Went to the liquor store and grabbed a half gallon of rum, and a 5th of rum. The dude only rang up the 5th of rum so my $30 purchase was $12 something. He bagged them both and I was on my way.

Honestly, would you guys tell him "Oh wait you forgot to ring up this item" or just count your blessings and walk away?