I used to buy peanuts-in-the-shell in 50 lb bags for the birds and toss scoopfulls onto the patio. (this "patio" isn't a people patio ... it was built simply as a place to put bird feeders - a great big cement slab).

I got tired of all the shells on the patio so I started tossing the peanuts into the grass. the crows didn't like trying to peck open the nuts in the soft grass so they carried each nut back to cement !!

I love crows .... they are sooo smart. And they recognize me. They know I'm the person carrying FOOD.