When prospects are looking for a neighborhood and a home to buy, they like to see the area amenities - as well as the people. So there is a desire for photos of playground with children playing, soccer fields with a game going on, schools with students so you can see what people are wearing in this area. But is this not an invasion of privacy? Many parents would not want to see a photo of their child on the internet, especially with the neighborhood noted. Blur the faces? Maybe that's not enough. Take photos early in the morning when no one is there? The photos don't come alive.
What do you do about this? How do you feel?

We were in Paris one year, around 1992 or so.
We went to a Park where there was a merry-go-round. The French parents would not let me take a picture.
Really, they went ballastic. So much for many visitors welcome!
Would it be acceptable to take pictures of people not facing the camera? And sports .. well, they would be far enough away that you could blur the faces without it being obvious, I would think.
My son and daughter-in-law are extremely private and would never consent to having their daughter's face on the internet, which is why I've never shared it online. Parents today have a heightened awareness of the danger their kids face. It sure is scary..
I always photograph without people.
As I understand it, there is no problem with respect to the law in taking photos of houses or children. You have the right, for the most part to take images of almost anything which is in the public view. I would be inclined to be careful when it comes to kids though. Just because something is lawful doesn't mean we shouldn't be sensitive. Perhaps you could take park shots from a far enough distance that kids are hard to recognize?
I found "Bert Krages, The Photgrapher's Right" to be interesting reading. It may be worth carrying a copy with you. People taking photos in public are being confronted on a more regular basis now.
I guess I can see the advantage of having a public place feel more alive with people. Having the legal right to do something doesn't make it the best thing to do. I wouldn't want my kid's photos posted on the internet, especially if it was connected to a particular place.
I once took photos in a retirement community to show the amenities of the area for a home I was selling. It made people very uncomfortable. I photoshoped out the people in the pool out of respect.
I try to have the people in the photos that I use facing away from me.
These are photos from this past week. Not the best photos, but they make the point.
Juno Beach Pier
Surf Fishing in Juno Beach FLorida
I think having people in the photos adds to the images.
Sharon, there's a lot of different thoughts about this topic (as I'm sure you can easily gather from just the small number of responses here).
I discuss this at length in my blog here:
http://activerain.com/blogsview/58739/Photography-1-1-Safety
Generally, there are two ways to look at this topic, from a legal perspective and from a 'what feels right' perspective. Sometimes they even coincide. :)
A very quick summary of my article:
Cheers, -B
Bill & Barbara Jo - perhaps you could blur them with a photo program.
Bryce - thanks for your comments and your link. It is nice when legal and right feeling coincide!