UGH! I'm so sorry, they stink!!!!!! I feel like this is one of those generational things. When I was entering the work force, over 20 years ago, it was UNHEARD of to flake on an appointment. I had so many jobs, so many interviews, there were codes of conduct on both sides. My little calendars and address books were packed into my car, driving all over hell and back. It was RARE that there were emergencies where people canceled, they always gave proper notice in advance. I hardly ever remember calling in sick or canceling things and I NEVER flaked. People knew they had to act a certain way to keep connections and a reputation.
By the time I left my job 5 years ago, honestly, the behavior you mention was practically standard among the 20's, 30's set. My friends and I talked about it a lot how we had never been afforded the luxury of flaking and ignoring calls and dodging emails and blowing people off with or without texts, like younger "professionals" for who it would be even EASIER with all this technology to give proper notice for stuff. I know not all people are bad now, but it has REALLY increased.
I think you will have to reconfirm the night before etc. I'm so sorry this happened to you, how awful! The bright side is definitely that these people are shmucks you don't want to work for though. Good luck job hunting and I hope you meet much nicer people soon!