Books have been set forth on this issue, and the controversy and arguments about where the "hot" one armed bandits are located in a casino are still raging – more than sixty yrs after slots were first added to the gaming floor in gambling dens.
The classic rule is that the more favourable slot games were put just inside the main foyer of the casino; so that everyone going by would be able to see actual jackpot winners … be aroused to come inside … play. Our inference is that this is no longer true.
Practically all of the major casinos nowadays are magnificent complexes … it is not possible to see inside from the sidewalk, so there’s no longer a reason to put the ‘loose’ slot games near to any doors.
An additional traditional rule is that loose slot machines are placed on the major aisles inside the casinos, again so that more people could see winning jackpots and be galvanized to play. Notably though, 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 slots 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!
Today, casinos are constantly changing their philosophy about where to place the loose slots.