It "could" speed up the creation of the other games. I'm not saying it "will" though. The idea is likely (I'm not saying this is what they are doing, this is only my guess) that when they finish this game, and start the next one, they'll just reuse all the maps and continue from there.
I've worked with RPG Maker for a while now and I will say that it's simple to make a game from scratch if all the assets for sprites and maps are already scripted and in place. You could technically finish the game tomorrow, take a copy of the game data and delete all the events, pick a different place to restart, and write a whole new story from a different character's perspective. The world already exists, and if the second game takes place at relatively the same time frame, there wouldn't be a need to add new area to the city (ie. new stores that didn't exist in the first game.)
When making games, it's definitely the easiest way to do it, albeit a lazy way. The game itself is not a graphically amazing piece of work, so the next game being in the same boat wouldn't really piss off too many people.
I've worked with RPG Maker for a while now and I will say that it's simple to make a game from scratch if all the assets for sprites and maps are already scripted and in place. You could technically finish the game tomorrow, take a copy of the game data and delete all the events, pick a different place to restart, and write a whole new story from a different character's perspective. The world already exists, and if the second game takes place at relatively the same time frame, there wouldn't be a need to add new area to the city (ie. new stores that didn't exist in the first game.)
When making games, it's definitely the easiest way to do it, albeit a lazy way. The game itself is not a graphically amazing piece of work, so the next game being in the same boat wouldn't really piss off too many people.