Ah, Borgman, I've missed butting heads with you!
With all due respect, my own personal opinion - and I don't mind if you or anybody else differs, that's what makes our two countries great - is that if your front yard is a potentially lethal space for a young child, or your favourite restaurant, then you have failed/are failing in your responsibility to your child to provide a safe environment in which to grow up.
(Feel free to be offended, but please understand I don't mean any offence, nor think any less of you or anybody; I fail to live up to most of the standards I impose on myself too, so it's not like I'm judging by saying that.)
"Did they take you across any busy streets while using SOME manner of restraint on you?"
Maybe they carried me before I was old enough to walk, and once or twice I can recall that they held my hand, but for the most part, no. I mainly remember them reminding me to look both ways, and coaching me on when to walk and when to stop, but as far back as I can remember, when I was walking, I was walking alone. (Hey, DJ, cue the emo-era Greenday!

)
"That just isn't an option for many folks. There have been many times since I had kids where not taking the kids shopping meant no groceries."
...really?
...honestly?
You had NO friends, colleagues, or family, or neighbors, who could nip out to the store and pick you up a pack of spaghetti noodles and a sack of potatoes?
None?
And you couldn't just order chinese?
Do you live in a mud hut in sub-saharan africa? No? Then I don't believe you. And if that's true, well... maybe having children while lacking any form of a social circle was a bad move, dude.
"So ALL forms of restraining your child for their safety are a substitute for proper parenting?"
See, dude, I'm fine with restraining your kid, I really am. But there's two things I'm fundamentally NOT fine with: those being a lack of freedom, and a leash on a kid. If you hold or carry your kid through a busy street, fine. But let the sucker go once he gets to the other side! Offering guidance is FINE, and commendable. But chaining the tyke up to a stake in your yard, I think, is unacceptable. And the only difference between chainging up your kid to a post to get his excercise, and using a leash, is that with a leash you're the post. The kid doesn't have the freedom to make his own mistakes, and as a result, is robbed opportunities to grow and to learn.
The other problem with leashes is, I will freely admit, one of emotion and perception. Leashes are used on dogs and in sex clubs. I do not see that they have any place on a healthy child.
A leash is a device for exerting and maintaining constant control over the object to which it is attached. I am of the opinion - and once again, I do not intend to offend, but I understand that some may be offended, and that is fine - that if your child
requires constant control, then you have failed as a parent.
Like I said though, I fail to live up to my own standards all the time, so don't get all hot and bothered. It doesn't mean I think any less of you; it's just the way I see it.