Some of those people are cheating - some of them are not. If the spot that you were creeping towards is popular then people will blind fire at it anyway. There many be far more cases when the person blind firing doesn't hit anything - but nobody will see those (unless they happen to be spectating them). The only cases that people see are the rare occasions that it works - and without any way to determine the sample size it looks like clairvoyance (or cheating).
It's the same effect as the stock scam: pick 1024 people and tell 512 that a stock will go up on a day, and the other 512 that it will go down. Drop anyone that gets a false predication and repeat ten times until some sucker thinks that you have a gift for picking stocks.