The only relevant part of the quote seems to be:

That twenty dollars has been anything from thirty to sixty-five dollars, the three or four times we've done this.

I'm pretty sure it's not that unlikely to come up ahead 'three or four' times when playing slot machines (if it weren't so late I'd actually do the sums). It seems much more plausible that the blog author was just lucky than that the machines were actually set to regularly pay out positive amounts.