Why don't they ask themselves any questions?

So many people on Facebook throw the most bizarre stuff out, claiming that it’s true, and people get all fired up and don’t even think about it.
One of my HS classmates shared a picture of obviously poopy pants. Looks like the kid had diarrhea. She claimed that a “friend” of hers has a 7 year old daughter who was in school and she had to go to the bathroom and the teacher wouldn’t let her and she pooped all over in her pants and had to suffer that embarrassment from 1:00 until school was out, AND on the bus ride home. No one bothered to call the parents to bring a change of clothes or to tell them their child was, obviously, sick.

Of course, everyone was outraged.
sigh.

I said I didn’t believe the story because the kids interact with multiple adults through out the day. Music, recess, PE, art as well as aides. If I believed it, I would have to believe the entire school was in on it and the bus driver!
“Oh, it happened! It happened to a friend of a friend! Go to her FB page. There are a million comments about it!” (The person with the FB page was not the person who it supposedly happened to.) I guess she thought if a million comments from a million other people who are as gullible as she is proves something.
She was insisting it was going to be on our local news tonight.
She also gave me the name of the teacher and the school district. Of course, there is no teacher by that name in the school district.
Then it turned into “He was a sub, and he got fired.”
Of course I didn’t find a single thing about it anywhere.
I think by the time I was finished commenting, my HS acquaintance was starting to finally question the story herself.

Why don’t people question this stuff?