i) Just because someone hasn't won in 10,000 times doesn't mean that the slot machine is not worth putting your money into. There is still a decent probability that a person will lose more that the mean or expected number of rolls for three Oscar
heads. If i flipped a coin three times and they were all heads, would you say that coin is biased and not worth a 50/50 bet at?
ii) This is just a single person. If this occurred numerous times, i.e. many many people with much over 30,000 rolls without hitting the jackpot then you may have a case (cf. Central Limi Theorem). But it is just one example.
iii) Another person may win it on much less than 6667 tries, 3 tickets each time, e.g. on their 100th go. Does this make it suddenly worthwhile? Of course not, but your example of one person not hitting it in however may goes doesn't make it not worth a go.
iv) It's gambling. There's always going to be cases where people get lucky and others don't. We don't know the odds of each (should be 1/20,0000 per ticket) and I doubt UR will publish the stats so you can't draw a conclusion from a single case.