My very first fight the guy shows up to the venue sticks for 10 minutes and bolts. We were up second, promoter comes up and is like yeah your opponent took want to fight this guy who is 5-2.
I didn't want to but I did, because that's what I came there for but that shit gets old. 
i think an opponent with a 1-6 record are more dangerous than 5-0. maybe not skill wise, but they have nothing to lose 
My first fight was supposed to be against someone who had 15 fights, but he left for reasons I don't remember. Then I took a short notice one a week later, and he also bailed for reasons I don't remember. I ended up getting a fight months later, but it definitely gets annoying. And this was on the amateur circuit, it understandably more frustrating for pros.
cmcgraw - Morally, maybe not. But those higher promotions (wsof,ufc,etc.) Only look at the record, not who you've fought. So I can see why its done. As stated it comes from the boxing model.
This isn't really true (well, I dunno about WSoF). I'm pretty sure the UFC checks who you've fought. Two things about it though are, they're almost never going to offer a roster spot to someone who is close to .500 no matter how good they are (obviously there've been a few exceptions), and they don't necessarily the check to see who you're opponents have fought.
That being said, beating up cans on the regional scene is fine, and at the very least it keeps you active, so it's better than not fighting at all.
The tomato can model is how boxing works with prospects, but it sucks. Sports are supposed to be competitive, especially when the athletes are hurting each other.
Ya most boxing prospects don't really take competitive fights until around the 20th fight. They usually build their fighters which builds a fan base, etc...
the better your record the better your competition should be.
i've never pulled out of a fight and have had so many cancelled, for every reason under the sun now.
i've lost money and now feel like a damned albatros
Those guys are always the ones who come into the ufc etc 18-0 20 -0 etc and then cant win a fight barely win a round in the ufc. If youre padding your record it only hurts you when you get to the next level
Kirik -
The tomato can model is how boxing works with prospects, but it sucks. Sports are supposed to be competitive, especially when the athletes are hurting each other.
This, If a guy gets in there overmatched and gets smashed its his fault if he gets hurt, not the guy who smashed him. However, to be an athlete and smash the hell out of someone you know shouldn't be in there with you, or to be a promoter and put someone in there with a person they shouldn't, is going to be not right to some people. It's the cans dumbass fault for getting in there with no chance, but it doesn't make it right for trained killers to look for scrubs to smash, or for promoters to put em in there knowing they're going to get hurt bad. I couldn't put cans in a position to get hurt bad myself by being overmatched, but its their own responsibility to protect themselves.