We had a Little Life backpack we used a bit when DS was first toddling outside as he was quite unsteady for a while and they helped stop him repeatedly falling over onto his face. We stopped using them as he became more steady and a bit taller making hand holding easier.
Probably my most strictly enforced parenting rule is that DS holds my hand if we are around traffic - so all pavements, car parks etc. He also has to hold my hand in shops, busy high streets, museums etc unless he's walking sensibly beside me, which is a rare thing as he is definitely possessed with the bolting spirit. It's bizarre as he is generally very physically cautious and extremely clingy. But give him the chance to run off into the distance without a backwards glance and he'll gleefully take it.
If we're on foot I am physically restraining him in some way most of the time - either holding his hand or if I need both hands at the till or to unlock the car I often have to hold him between my legs.
To be honest I don't really see any difference between me having the physicallly hold him back whilst holding hands or in a knee grip compared with having him on reins. It's still physical restraint isn't it?
I still use the buggy a fair bit and whilst that is sometimes because we need to walk further or faster than is realistic with a toddler it's also often used as a restraint - trips to the shops are much easier if he is in the buggy.
I've never understood the judgement about using reins, it seems no different to using a buggy or other direct physical restraint (carrying or hand holding) to me.
And yet I've got a set of reins in the house that I never use. I am honestly not sure why that is. Maybe I fear being judged?
(Based in London by the way).