My mom did it with my sister when we lived in a major metropolitan city, very very crowded. That was also like 20+ years go and in Asia so I have no idea if it's a taboo thing in modern Western culture or not?

I've heard of parents who will do it at Disney, etc using those backpacks with a leash. Some days I do feel like it's a great idea b/c my 15 mo old refuses to hold my hand and just runs all over the place lol!