I think that we are only ripped off when you buy an item from a supplier only to find that the same item would have cost you half that much if bought elsewhere.
I'm not talking about a 5 or 10% difference, I'm talking something like a whopping 50% difference, now that annoys me no end

I got caught out buying a submersible pump, forgotten what I paid for it now...was something like £140 and I saw the same pump on another suppliers site for roughly half of that price..and it was a much smaller supplier too!
As for it being a trade...well no, it isn't specifically a trade is it? It is semi-skilled howeever it does take a great deal of skill to do a top job very quickly.
There isn't that much to learn about the craft of window cleaning.
Over the years well over a 100 people have worked for me, some for no more than an hour or two and a few for several years.
Although it generally took a day or two for them to know how to use a squeegee effectively, it still took them at least 3 months before they could fully be trusted to do a decent job consistantly and also to be able to clean at a reasonable speed.
to begin with I would clean the entire upstairs and 3/4 of the downstairs too!! they would probably be just about starting on their 3rd window as I was finishing my tenth or 11th! And I still had to go back over their work picking up mistakes

With WFP it is a simpler process for sure, quite literally anyone can rub a brush over a window but doing the job properly takes some doing, developing an effective technique takes time and getting fast at it also takes some doing, we are constantly hearing on the forum of awful WFP results, and I've seen a fair bit of it myself.
Because it feels so easy to do, so often the job doesn't get done properly, ergo, many don't continue to really develop what they are doing INTO a skill.
The other day i was cleaning the inside of a large and difficult office; over the road was a guy cleaning a house the trad way, this guy was one of the first people I ever emplyed over 22 years ago (the first one is a total twot and he's still going strong by the way).
This guy quickly whipped his ladder of the car, walked briskly up to the house, ladder up in a flash, and him up there after it...
Steeply sloping garden, ladder up against gutters and he's up there and striding up and across a steeply sloping, mossy roof to his first window.
Ok, I was wincing at the health & safety bit, but was impressed at how efficiently he got on with it...until he started to clean the window...
Nothing wrong with the way in which he cleaned it, and I'll bet he did a top job too, but my god, he was so SLOW!!!
I was doing the inside of a BIG georgian window, I went slowly at my window as I was interested in watching him work, I'd finished the window and stood there for a while watching him, then I had to go to the next office as the guy working in the office kept looking up at me wondering what the hell I was doing! (I could see his reflection in the gleaming window I'd just cleaned!

)
So I gathered my gear together and went into the next office and did two smaller windows and he was STILL on the same window
This guy has come back into window cleaning after nearly 20 years, but oh boy, is he slow or what
Doing a top quality job in the shortest possible time is where you really need to be skilled, and it isn't about working hard and putting in lots of effort, this guy was doing loads of that.
As Squeaky will tell you, even after several years he is still getting quicker, so it really does take time to develop your skill at the job we do.
Ian