Why pay for and deal with the hassle of changing dirty diapers, when you can just have your child urinate/defecate directly on the street/bus/supermarket floor (or if feeling industrious, hold them over the trash can)?  Then it's someone else's job to clean that up!

In Western countries, babies are naked too, while at the beach.

Butt......, we change diapers. Chinese seem more 'practical' with open crotch pants.

What is 'scrotch'?anyway?

Can you imagine, China enacting Law about 'pet owners must clean pet feces, while in public areas'? Used plastic bags are everywhere, anyway. Pet owners should just get small 'pick-up tool'. 

I'm glad I knew all this stuff before I came back to China, less culture shock. TIC. I had to lift my foot many times while shopping.I tried to tell my GF that I pick up after my dog, no response. I did see a woman pick up after her dog and toss it in the trash.

 It's not just China. I worked in a small town, Ontario. When I did the bank deposits downtown, I had to dance around the dog crap on the sidewalk everyday. Everyone that lives DT walks their dog at night, but never pick it up.

 I was petting a loose Samoyed dog once in Guilin on the walking streets, when the dog pitched one. I was tempted to watch the reaction of who ever stepped in it, but didn't.

Kids peeing everywhere (streets restaurants, etc.) is just disgusting. I remember siting in a Chinese restaurant in Beijing, with a friend who just came to visit me here and there was a family sitting next to us. In one moment, the kid starts peeing on the floor next to our table, mom claps her hands and shouting, she is proud of him, and then a waitress takes a tablecloth from another table and just puts it on the floor. We were disgusted by this behavior.
Another story. I am staning in the subway and out of nowhere a kid starts to pee on the seat, next to and old grandpa. Kid's grandma starts scolding him and shouting. She takes out some old newspaper and covers the seat with the pee. The grandpa just sits there, not moving.
Kids with crotchless pants just amuse me. They sit on everything (ground, floor, benches, subway seats), any time of the day and isn't it simply not hygienic to expose your private parts to dirt and germs?

The "bright side" of this situation is that there are fewer disposable diapers going in to landfills. Jus sayin'

My only request is that parents aim for those squared off areas on sidewalks where trees are planted and the dirt is exposed. I don't enjoy stepping in baby urine on my way to work...

The thing that bugs me more than the pee/poo on the street is the fact that this bare part of the kid is also what it touching the seat on the bus/restaurant etc. The kid can scratch itself and then put its fingers everywhere that the rest of us might need to touch. 

 It sounds like I'm not alone who's trying to make sense of all this peeing & pooping around. 

It's better that Chinese don't learn to use diapers, because if they do...we will walk on carpet of diapers.

how do babies/small children pee in their homes, bathroom or living room floor ? 

Chinese do not use diapers for probably two reasons, less obvious to save money, more obvious to develop the so called Elimination Communication (EC) Technique. This is a practice in which a caregiver uses timing, signals, cues, and intuition to address the need to eliminate waste. Caregivers try to recognize and respond to babies' bodily needs and enable them to urinate and defecate in an appropriate place (e.g. a toilet). This leads to saving money on buying diapers.
(Wiki) It is funny that is says toilet based on what we see here. A toilet can be anything: a nice tree in a park, a restaraunt's floor, street side.

I had a baby in China & he never wore those crotchless pants. I brought baby pants from Russia, went to the tailor's, gave him a sample & he made a dozen of  Russian-style pants (baby's private parts & feet are covered).  I couldn't afford to buy diapers, so I just changed him 10 times a day & started potty-training him when he was around 6 months old.

 So, my point is, don't be lazy, change your babies, teach them to use the bathroom or tell you when they have to go. No one wants to see your baby's genitals.

It'll be a cold day in Hell before any child of mine will be dressed in them. Can't help wondering how many inteligent children reach a state of self awareness whilst wearing them in the supermarket. "OH MY GOD! MY ARSE IS HANGING OUT! WAKE UP! WAKE UP NOW!"