My son runs in the different situation away from me.
No matter whether I am standing at the checkout when shopping or whether we are on the car or simply walking just walk.
My son (27 months) turns around once more smiles at me and expected that I should capture him. I think for him it is a game. I have explained to him many times that it can be dangerous! And he must stay at mom.
But it changes nothing. Last week we were almost dangerous! In a situation.
Have you tried one of those animal backpacks that the tail is for a lack of better words a lead. I swore I would never use one for my son, but he did the same thing and I was scared for his safety. He hated it and soon learned that if he could earn my trust he didn’t have to wear it.
I also use to run off from my parents, and one day in a safe situation(on the wol-co store, i can still remember it) I took off in the clothes section, my parents hide behind a rack of clothes and I couldn’t find them. I started to cry and they came out saying how scared they were that they lost me and that is why I should never take off. I was about 3ish. I never ever took off again.
Best of luck