I think the most interesting part of this is that people treated it as an experiment when the externalities of gambling were widely understood and very negative

I think the most interesting part of this is that people treated it as an experiment when the externalities of gambling were widely understood and very negative. Even in the well regulated cases things like state lotteries they are effectively taxes on the poor, and the best arguments we've got are "we should let anyone do what they want" - sure, but we shouldn't make it easy for corporations to exploit anyone in any way they want. If you want to setup with a local bookie and deal with that you're going to filter out a huge portion of starting gamblers.