First of all,you're doing the right thing by staying away from gambling.My Dad and Uncle didn't make a lot of money because they could pick winning numbers. They made a lot of money because their customers couldn't.

As far as your question,this is only my opinion, but I would imagine that no matter what period in history,there was always someone to take gambling action.

Generally speaking,sports books take racing and sports action,while numbers guys take numbers action. That doesn't mean that one guy couldn't take both (or more). It just means that each is kind of a specialized operation . In an illegal casino,for example,you can shoot Craps or play Blackjack,and in all probability ,play a number and get a bet down on football or racing if you want. A lot of these joints are "one stop" stores.

Back in the old days,you probably could get a numbers bet and a horse bet down with the same guy,because one of the common methods used to determine the winning number was either the order of the first three horses in a designated race,or a number based on the total "handle " for a designated track.(usually the first three digits to the left of the decimal point).
Other methods were used as well,this was just a common one .

Throughout history,going back hundreds of years if not more,there has always been some form of game in which you could place a bet on the outcome of a particular number.Only the methods of picking the number and the operators of the game have changed.

Just my 2 cents worth.