Tony doesn't view it, as missing out, when Anne has sex with other people than him. He wants her to do all these things, and gets really turned on by the idea of her having sex with other men. Even when she goes behind his back and he finds out about it, that turns him on as well. So it doesn't matter to him, that he's having less sex with his wife, because ultimately she's doing what he actually wants. He's getting what he wants, she's getting what she wants, so both of them are winners.
You on the other hand are seeing it from your own perspective, where having less sex with your partner, would make you the loser. The problem with that, is that Tony doesn't see it that way.
In most of those incidences that you mention above, Anne does eventually tell Tony about them unsolicited, when they're in bed together. In some cases, it's weeks after the fact. But she does tell him about them. And when she does, he never demands to know why she never told him about it immediately. And that demonstrates, that as far as he's concerned, she has a free pass to do what she wants, and decide whether she tells him about it or not. When they're on holiday in Barbados, that all changes though. Because both of them now, have to tell each other what they get up to apart. And if they break that pact then they will be cheating, and I assume it would lead to serious consequences