Life is like one big human zoo.
All sorts of critters, some are cute and cuddly, some are mean and nasty. Some are downright funny to watch, others are downright facinating. Some one does not understand, takes a bit to figure out what makes them tick. Still one can learn from all these various critters , may not like them, still one can learn something.
Internet - well the Internet and forums are nothing more than what we have had forever. Folks getting together sharing a common interest(s) and interacting.
The old guys sitting in benches playing checkers, whittling - talking about politics, kids, honey-do's, weather, and trying to figure how best to fix a car, get rid of a weed, or talk momma out of doing wallpaper in the kitchen.
Ladies, having quilting bees, discussing how to con the hubby's into doing the wallpaper, getting grandkids to eat veggies, and what in heck can be so interesting about a guy taking apart a lawnmower he found for $10 that won't run.
Kids on the playground, discussing the new cereal, coolest tennis shoes, and did you notice the teacher was wearing one blue sock and one brown one?.
In any group - some don't fit in. One guy cheats at checkers, and then lies when caught. One fella gets offended when he is asked for the umpteeth time to watch his blade while whittling.
Ladies get offended when a lady keeps on whining about about being beat up by her old man- she will not listen and disrupts the fun atmosphere of doing a quilt for charity.
Talk of divorce after 25 years of marriage is - horrors, if the fella wants a Trophy Wife, hell hath no fury like a bunch of women. If the same group of women suggest the lady is nuts for wanting to leave a good man and share perhaps it is HER hormones acting up, well that ladies group is just plain nuts and don't know nothing and leaves the group...badmouthing them as the slams the door on the way out...
Kids have bullies, to deal with, kids get upset when parents tell them to do chores for extra money for that new toy they want. Kids take sides on the subjects and more inner groups are established.
Some groups just ask a person to not come back - nicely. Other times they are shunned and ignored. Some folks leave a group, and rightly so. Then again sometimes they talk bad about a group asked to leave from, lie about the reasons they no longer hang out with the group - cannot accept being crtiticized and thus have to qualify reasons for their actions.
Internet just speeds this up, and involves a bigger group of folks to participate is all.