If you can't grasp this then you'll never make it in any walk of life. My mortgage being paid relies on people paying me for my knowledge and expertise. With the free distribution of information afforded by the internet my (and your) pool of work is shrinking.
Not knowing how to do something is no longer and obstacle for the diyer. Now our customers consist of those too busy, too lazy and physically incapable of doing the work.
Our knowledge allows me to cloth and feed my children. That being said I will still give someone a little advice if asked. You think that person shouldn't show some appreciation? Wow.
I don't know why you're making out the members with access to the plumber's arms are some kind of arrogant, elitist bully because they're not. They're just professional plumbers.
You can't swear on the forum but you can be direct and honest with someone. Whether they have a tantrum or not is another matter.
Plumbing is and always has been a business, I take it seriously as all plumbers should. I'll help another plumber if, and only if, his customer base doesn't overlap with mine. Likewise i'll see a member of the public pay another hard working plumber to do a job before I hold their hand through it and no-one gets paid.
If it's a hobby for you then great, just don't preach to the people who are walking the walk. It's a bloody hard game and i'm not in it for fun, social consciense be damned.
As for your last post, all I can say is you display an absolutely shocking naivety which will evaporate in the first year of trading if you manage to make it that far. I just hope you don't have a family relying on you to make a living out of being a tradesman because they'll starve.