You used to be able to upgrade your entire gold subscription to gamepass by just paying for a month of gamepass. I know of people that bought multiple years of gold while they were on sale then bought a month of gamepass and boom, multiple years of gamepass for a low price.
I'm not sure if they still do that upgrading thing anymore
I feel like that was a great scheme to both lock a bunch if people into years of gamepass really early on and bump up their numbers, at the same time as rewarding the loyal Xbox Live subscribers who got a great deal out of it. Win - win.
Yeah, I pulled some loophole with gold and live and conversion a few years ago, and it's absolutely been worth it. The titles I played alone covered the cost of it all, especially because I played games I otherwise wouldn't have. The game where you drive trucks in mud? Not on my shopping list. But for "free"? I'm in, let's waste some time.