It's not that I think it's inconvenient, it's that I think it's not needed. Yes, they are my kids and my responsibility - but I also consider it my responsibility to teach my child independence. You say, how hard is it to walk them 2 or 3 blocks and stand there for 5 minutes - I ask you, how hard is it for an elementary age child to walk 2 or 3 blocks and stand for 5 minutes? My child doesn't walk in the street (sidewalks the entire way) and the chances of being abducted are next to nil - so I don't worry about it. I also don't worry about him being struck by lightening when it's raining out - could it happen? sure, but the odds are so against it that I'll save my energy for things like making sure he fastens his seat belt or wears a helmet while riding a bike.
If you want to wait a while longer before giving a little space to your kids, that's your choice, and in the end I'm sure both our kids are going to be just fine, but there's no need to get all "shocked" about how other parents do it. Just because I choose to go the early independence route does not mean that I consider my child an inconvenience, I'm irresponsible or I don't love my child as much as you do. I just have different priorities than you. Neither is right or wrong.