His factory needed a stable workforce, more so than most at the time -- because one screw-up could stop the line. And he was willing to pay for this. Hire the most stable, least-drunk, workers around.
Of course he wasn't above some good PR, either. (And this was also the era when you could get a patent on a perpetual motion machine, right?) He'd be thrilled to see his PR quoted uncritically a century later.
This shift to more stable employment wasn't all gravy, by the way. In a factory town where the average guy keeps a job for a few months at a time, a recession means that it takes him a bit longer to find the next job... everyone's looking at the same time. But in a factory town where the average guy keeps his job for decades, layoffs are much more serious. Which is part of why the "great" depression gets this adjective in out memory, and others don't.
> At the time, workers could count on about $2.25 per day, for which they worked nine-hour shifts. It was pretty good money in those days, but the toll was too much for many to bear. Ford's turnover rate was very high. In 1913, Ford hired more than 52,000 men to keep a workforce of only 14,000. New workers required a costly break-in period, making matters worse for the company. Also, some men simply walked away from the line to quit and look for a job elsewhere. Then the line stopped and production of cars halted. The increased cost and delayed production kept Ford from selling his cars at the low price he wanted. Drastic measures were necessary if he was to keep up this production.
https://www.forbes.com/sites/timworstall/2012/03/04/the-stor...