Why the truth is not in them ??

I wonder how many people have been told something by a buyer, that was no where near the truth....I hate to think how many times I  have been told that I will send a Pay-Pal tomorrow, or I'll send you a check tonight....and never do anything of the kind.....I've been waiting for two weeks for a check from a guy in Michigan  , I have sold a item 13 times on another web-site based on what a person has told me and never received the first penny..........Does anyone tell the truth anymore ??   I have one web-site that I do business on that has a 98% negative truth rate.....Isn't that a poor way to deal with people ??     What are your experience ?? 
I had an experience 2 months ago with a man who turned out to be a middle class realtor in his 40’s (I looked him up).
He agreed to buy an amp from me, lowballed me and I agreed to pay the shipping as well. He was supposed to pay the paypal, or else use another method.
He sent me the money via paypal right away, minus the fee which was another $50.00. I didn’t touch the money, and immediately wrote him back saying that wasn’t the deal, either pay the fee, or go friends and family or send a check.
Within seconds, he sent me a flurry of emails calling me a crook, a thief and a scamming little b---h.
Civility and reason are just non-existent with some people. It was very upsetting.
There was an old cartoon they used to show back when they had driver's ed classes in high school. It showed the Disney character, Goofy, as his usual, amiable, goofy self until he got behind the wheel of his car and then he became a raging A-hole. 

It's gotten to be like that with the advent of the internet. Feeling safe and unassailable, people tend to turn into a not so nice version of themselves. Some even go several steps further. 

The problem is, after doing it for so long, they maintain that persona out into the real world, which explains a lot of things as of late.

All the best,
autospec, I didn't mean anything against your OP, in case you read it that way, I fully agree with you. Years ago, before internet, I advertised and instrument for sale at FIRM price. A man called and we agreed the price was firm. He came over with his son (whom it was for). Afterward, I got the feeling that he was going to "teach" his son how to do business. They came over, and the man tried to bargain down $60. After his haggling, I reminded him the price was firm, and he's only bargaining $60 less. So his tactic was "yes, we're only talking $60 less, so you should take it". I then said that it was no longer for sale. Then he finally "gave in" at the full price. I reminded him "sorry, but it's no longer for sale, please leave". He even phoned me after they got home, to please sell it at full price. I didn't. I was congenial all along, but keep agreements.
The clincher of that story is, I told him "we both know this is a very good deal". Some people are not happy unless they can haggle down, no matter how good of an initial bargain. 
@isochronism ,

’Some people are not happy unless they can haggle down, no matter how good of an initial bargain.’

Yes, but now we’re being advised by consumer groups to haggle down on all kinds of things ranging from vehicle insurance, energy provision to broadband contracts.

I personally don’t like it, and I don’t have the personality for it either, but some colleagues at work actually boast about how much they save this way.