It absolutely is "somebody's business", when the state is either running it, or enabling it with heavy legislation.
Banning gambling outright is an obvious way to make gambling black market. But we can take commission reports like this ( https://govinfo.library.unt.edu/ngisc/reports/7.pdf ) and determine best practices how to minimise gambling's impact.
1. Commission recommends that states, tribal governments, and pari-mutuel facilities ban credit card cash advance machines and other devices activated by debit or credit cards from the immediate area where gambling takes place.
2. (State, local, tribal) they should recognize that, especially in economically depressed communities, casino gambling has demonstrated the ability to generate economic development through the creation of quality jobs.
3. (States, localities, tribal) should recognize that lotteries, Internet gambling, and non-casino electronic gambling devices do not create a concentration of good quality jobs and do not generate significant economic development. (Think of this as video slots in corners at gas stations)
Not exercising and getting fat also affects lives of everyone around the fat person, does that mean we should force individuals to exercise every day ?
Also it is much better if the addicts are identified early and quickly so that people could stay away from them and shun them instead of a woman figuring out her husband is an addict after the marriage. After gambling addiction next what sugar addiction or netflix addiction ?
Unless we move it into a class of things which include for example, public health or public safety, in general things that place a huge burden on a large number of individuals for the sake of a small number of individual beneficiaries. For example, we limit the claims that people can make for medicines, we don't require that individuals research every medicine that they take.
Maybe the danger of sports betting is so concealed that we can't expect that the bulk of consumers can realize that danger until they have already been hurt (I'm not making that claim.) Wouldn't you expect a government to regulate in that case?
Addictions in general tend to breed other, more problematic crime. Nobody feels bad for a junkie who blows all their own money and privately ODs in the street. People get really freaked out when a junkie is robbing people in the street to pay for his fix.
>And the longer view, is more people will be impoverished with more easy to obtain gambling
As long as they are doing it out of their own choice it is nobody's business.