The 'mugs game' line is a bit too catch all for me, as there are numerous ways to gamble and not all of them are for mugs.
If you're gambling on casino tables and slots over a long period of time, then you're only ever likely to come out as a loser. Casino games and slots have a return to player (RTP) percentage attributed to them, which will never be as high as 100%. A RTP that is less than 100% means the house always win in the long term.
In a game of European roulette, the numbers are 1 - 36, so if you put £1 on number 1 and it lands, you'll be paid back £36, which makes the odds of that bet 35/1. That would be fair if there were only 36 slots on the roulette wheel, however there are 37 slots as there is always a green 0 there too, so that's what makes your £1 bet on number 1 a poor value bet (even if it subsequently comes in) because you're taking odds of 35/1 on something that is actually 36/1. The same 'house edge' applies to all casino table games as well as slots, and means most people end up as losers, and the longer you play the more likely you are to be a loser.
The difference with sport betting is that you, as a punter, can have an edge. You may know a lot about horses and have contacts across a lot of stables that give you privileged insights into how likely horses are to perform against the odds the bookmaker is offering. Much closer to home, there were quite a few on here who, around January time, started backing us to get relegated at odds of 80/1, as they had a more knowledgeable position on how bad we were performing and how bad the trajectory was. Those 80/1 bets ultimately lost, but a few weeks before the season ended the same relegation bet was being offered at 11/4, so those that had got on at 80/1 had a profitable cash out exit point but more importantly had been shown to identify value, which is basically what it's all about. Essentially if you have a way of constantly identifying value (where the bookmakers odds are more generous than the actual probability of the event happening) then you are no mug and you can turn a good profit.
In the case of Toney, if he was making considered 'value' bets and using insider knowledge to gain that edge then that is one type of problem that warrants a certain level of punishment. If he was just throwing money on willy nilly to feed an addiction and get a fix then the punishment needs to be very different and what he really needs is help. Even if he was banned from betting for life then there's still a chance he and others in his situation could just wander into a casino and start throwing money onto roulette with the same damaging consequences.