Because it's the highest selling game, so Gamestop puts it out there. It's just funny that exdeath can't go more than three posts without hating on those two franchises for being mainstream, yet he is all over Final Fantasies nuts. Like final fantasy didn't become mainstream or something.
Actually that's not why. You're flat out wrong. They don't put them there because they are the top selling. Madden is barely holding on these days. It barely even cracked 4 million in sales in North America across all platforms. So it's not sales.
It's money. That's it. I used to be a manager at Gamestop and I was told by a non gamer who happen to be an area or district manager what to put above the register and what to fill X space with. Even when we would collectively go as managers and put our best effort forward to explain what our customers are buying and what games are excellent titles, trying to get a little bit of leeway to do our store a little differently based on our clientele. It was because some company paid some cash to get their game up there. Not because the game is any good, not because of sales, and not because that's what your store's demographic is interested in.
When I was there, my store had a lot of Fighting Game and RPG fans(we sold out of Soul Calibur 2 on every platform on the first day and had over 300 reserves on the Gamecube alone). We got standees for Final Fantasy and Suikoden. We got posters for the new King of Fighters or Street Fighter title. We never got to put them up because they were pushing such classics as "The Incredible Hulk" and "The Matrix" /sarcasm
I guess you could say that today it's more about money than the quality a good bit of the time. It's less about the games and more about "how many DLC packs will it have in the first year" or "how many people will be playing online and buying junk food for double XP". Back when the 8bit/16bit era was in full swing gaming was more niche and not so mainstream. Not as much money, many great publishers back then blew up and got greedy or swallowed by others.
More about selling your brand than selling a great title.