Many years ago I worked at a company that had Ladbrokes in the UK as a customer. On my first visit to London, I noticed their storefronts and found them appalling. They were some of the sorriest, shabbiest public spaces I'd seen, clearly designed to extract resources from the least well off.
I don't really buy any of the arguments in favor of widespread legalization (and I include state lotteries in this). I could be ok with legalization for a few big events like the NCAA tournament because clearly there is some demand that must be met, but we should not be enabling gambling as a widespread daily habit.
Of course there will always be black market gambling and the state cannot protect its citizens from every evil, but nor should it actively enable them.
But these commercial gambling halls, it's not some well of person who decides to pop in Friday afternoon and maybe lose €20 on a crazy sports bet or the slot machines and then go home and have dinner with the family. It is the some of our weakest and loneliest people who line up, waiting for the place to open and then spend the next 10 hours there. There are places who will provide free food for their best "customers", to ensure that they don't leave. We're transferring money from social welfare to private companies, using addiction and loneliness.
As for sports, I don't think professional soccer would like a ban on sports gambling. The revenue and salaries it have generated are to high for them to walk away now. It is hurting the sport though, in the sense that the community and local fans have been pushed out long ago. A local football club had to leave the premier league a few years ago, as a result they could no longer charge insane prices for tickets at the stadium. The result: They had more fans come to every single game, they sold more season passes, because the fans still wanted to see the games, and now they could afford it. Sure, they made less money, but the connection to the fans and the city grow.