Books have been set forth on this item, and the conflict and feuds about where the "hot" one armed bandits are located in the casino are still ongoing – over sixty yrs after one armed bandits were 1st installed in gambling houses.
The standard rule is that the better slots were put just inside the main entry of the casino; so that casino fanatics passing by would be able to see real jackpot winners and be baited to come inside … play. Our inclination is that this is no longer true.
Nearly all of the major casinos nowadays are magnificent complexes and it’s no longer possible to see inside from the sidewalk, so there’s no longer a reason to put the ‘loose’ slots near to any of the doors.
Another standard rule is that loose slots are put on the major aisles inside the casinos, again so that more fun seekers could see winning jackpots and be roused to play. Importantly however, we find that this also is no longer a universal rule.
What casinos found over the years is that people walking down the busy aisles were frequently on the way to somewhere else. If they played the slot machines at all, they would simply put in their loose change because they happened to be walking by. Win or lose, they would very often not stop to keep playing. And the last thing a casino wants is for someone to win a jackpot by playing only a few coins and then not stay to put it all back in!
Nowadays, casinos are constantly changing their perspective about where to place the loose slots.