One has interviewed me a few months ago and told me things like "great feeling, I feel you're motivated, hit me up in a few months and we'll hire you". I wrote to him as expected, never got an answer. I called a few weeks ago, he said he'd call me by the end of the week. I called once again after that, his secretary told me he'd call back. Nothing ever since.
Another has interviewed me on the phone for thirty minutes and told me his company was interested in hiring me but I had to do a test project first. So I woke up one Saturday (I was working full time at that point) and spent a day working on said project. I sent it and was told it would take two weeks to get a reply since the guy who was to review my project was on vacation. Three weeks later, I ask for some news. No reply. Two months later, I ping back: no reply.
Another is a friend's acquaintance. He's a freelance entrepreneur. We ate pizza and discussed about working together a few months ago. He basically told me "yeah, call me when you're free and I'll introduce you to the tech I'm using". I write to him and he says "right now I'm working on this and that, what about you? When do you want to come?". I tell him and get no reply.
(I have more examples in mind but have to stop here because of the length limit.)
For a few months I didn't care much, but I'm slowly starting to understand that most companies are just like that, rude and unrespectful. If you don't like me, why do you make me believe that you're willing to hire? And what does it cost you to tell me 'no'? You're not busy to the point where you can't do this. So yeah, what do I do with those addresses? Spam lists? Fake outstanding applications where the fake candidate never replies to them?