Gambling has always been a part of football. You mentioned the football pools, is this not gambling? Horse racing, not going to mention that?

Conflating fixed odds machines with sports gambling is deliberately disingenuous, it is like comparing a nice glass of water with super skunk weed. Sports gambling is known to have less harm because it is not possible to control many aspects of the experience, unlike with fixed odds machine where the experience is controlled to appeal to addicts. Also, these machines are very heavily regulated, there are categories that separate what places can have them, how the mechanics operate, etc. We have regulation (you seem to be unaware that regulations have changed to limit how much you can wager, you cannot wager £50 in 5 minutes), the problem is purely one of choice.

Online gambling has grown because it is more accessible, and that has meant that a higher proportion of the users are people who didn't want go into a seedy shop and can now put their acca on at the weekend and that is it.

Football pools was also about extracting money from people. The people who ran the pools did not do so because they had an innate love for the human spirit, they did it because people wanted to gamble.

Also, banning advertising would not be a big issue for gambling companies. In the UK, it would be a massive leveller because Paddy Power is able to generate as much revenue as everyone else whilst spending significantly less on advertising. However, the issue is that offshore places would still advertise in the UK and it would significantly incentivize revenue generation from FBOT. If you no longer have big retail participation then you have to rely on addicts to fund the company. This is the first-order effects, past this point it will be different and who knows. But there is an ecosystem that advertising is part of that generates massive revenue, provides significant employment, funds addiction treatment (until 2022, there were no gambling addiction centres funded by the government, it was all funded by providers), and is a generally low-harm product that people enjoy (gambling has been a core part of British culture for decades, what has changed recently is the makeup of British society not gambling).