I would be all for making sports gambling legal and unrestrained if society wasn't expected to pick up the mess if something goes wrong. The same argument with drug legalization: if we are morally on the hook for millions of dollars in rehab costs, then no, you shouldn't be allowed to do hard drugs. Alcohol and tobacco use are similar vices where I'm not ok with unrestrained access if society is expected to provide the resources to pick up pieces of bad results. Freedom with responsibility for your own actions is fine, freedom without responsibility is not ok, it simply isn't a feasible option.