If this business is so lucrative, why isn't organized crime involved? It seems like a field where they have a number of comparative advantages:

1. Good at negotiating with local businesses. 2. Good at motivating low-paid employees to handle large cash sums without pilfering. 3. They love cash businesses. 4. More tax efficient than people doing 'side hustles'. 5. Good at managing kick-backs to eg. motel staff.

My guess is that the most 'gold mine' locations are already controlled by entrenched players who defend them using a variety of legal and illegal methods - vandalism of competitors' machines, high rents, kickbacks, threats to landlords.

Then all the marginally profitable locations are competed over by amateurs who routinely lose money and get disillusioned.