I hit one the other day with my cart because she (?) thought it was okay to stop dead-center infront of me because it's condishuns caught up with it. Not even kidding, she just stood there leaning on the cart. I usually wouldn't get so close but 1) they waddle at a "holy-shit-this-can't-be-real" pace and 2) I saw an opportunity to hit one with my cart and seized it. Just kinda went "jeezus, sorry didn't know you were gonna stop right here -shrug-". That thing was planetary, probably didn't even feel me hit it, either that or its used to things getting stuck in its gravitational pull.