Also Nata, I appreciate you sticking up for me - of maybe just sticking up for civility on this Board. I'll admit that I'm having a little more fun ruffling the pro-leash'ers feather because I know that nothing I say will really convince them otherwise.
If someone wants to attack me for admitting that I've had a few panicky instances when a child wonders off - fine. I'm not ashamed of that. I think this happens to every parent once in a while. It's not a reason to put them on a leash. It's always a little risky introducing children into the bigger world, but it's our job as parents to do that in a reasonably safe manner. Parents set rules, hold hands, don't run, timeouts, etc. A leash is a lazy aid that doesn't set a good message.
Could there be exceptions? Sure! The poor one-armed dad with twins comes to mind - yikes! - and I'll also concede that I've never handled twins even with two arms but I can see how that would be really hard. But sadly, most of the parents I see walking their kids on leashes don't have twins, and they're just preoccupied with other stuff. It's just one more lazy convenience, like plopping your kid in front of the ipad at every opportunity (oooh, now I've done it!).