however when the word "buy" is followed by the name of a good, not a service, (i.e. "buy a film") it is interpreted in trade, legal and common terms as acquiring ownership rights to that good.

Thats why you’ll never see “The word buy followed by the name of a good”. In fact, you probably won’t even see the word “buy”. Most commonly you’ll see “add to cart” and then “check out”. Which are coincidentally the same words you’ll see when buying a movie ticket.

If you can “buy” a movie ticket which allows you to watch a movie on a temporary basis, you can “buy” a license to play a game on a temporary basis.

This isn’t even a new, online marketplace problem. Even when you were buying physical disks, you were still purchasing a license, not the game in perpetuity.