Because I hate renting games. I can't explain why but I hate it. Tried Gamefly and legit the only shit that was ever available without a huge ass wait seemed to be shit already old as hell and in the bargain bin. Also I take my time on games so most of them go well past a month for me to play so I end up really paying closer to 45 for that game (not really applicable in this case though). And as far as subs goes... I really try avoiding subbing to a million different things. Because 15 bucks here and 15 bucks there adds up, and my senile ass always forgets to cancel. Like Hell I probably have a wow sub still active somewhere that I forgot about. I may buck that and try the EA sub because legit 15 bucks is a good price for a game like this, and I'll probably enjoy it that way.
And on the other about the length: That's why I put +10 in parentheses, because that's what I heard too was a ~20 hour game. That's still too short for my tastes at full price. I'm like you, I get my money's worth. I have 1k hours in Nioh, hundreds in Souls III and Bloodborne, and hundreds in Fallout 4. So I just kind of disregard games that tout anything less than 80 hours or so. IE Why Greedfall and Outer Worlds lost my interest as well. I just look for something completely different than many people when it comes to games.