Common sense, Toho Monsters and making money

You are spculating tat buying rights to the TOHO monsters would be a bad decisi because it wouldn't be cost-efficent but now that Godzilla has returned. More people are intrested in the franchise and might be more willing to watch the sequal. Just look at Transformers. 

Mecha Rodan has a point. They are bringing back old Transformers from the old cartoons and toys in the new movies. Sure people don't know, but they don't care, they want to see optimus Prime get into a fight with other robots. And that's essentially why Godzilla is so big now, people want to see giant monsters fight.

You have a point in that it costs a lot to buy the rights. But the potential profit may be worth the risk.

yes mecha rodan has a pint and buyng old monsters thatpepole don't even know is a good thing general audiances migth think that its acctually a new monster

Sounds accurate but I think Mothra is pretty recognizable too, I had friends who were not Godzilla fans who were hoping for Mothra to be in this movie.  I think they're trying to start a new era of Godzilla movies and with that comes a revisiting of the popular characters.  Mothra, Rodan and King Ghidorah are all hits and popular, so it might just be more profitable to tap into that popularity than to try to create all new characters.

What if Toho made it a requirment in a contract that Legendary had to use their monsters for a sequel? I think some of you are forgetting that Toho is also making a lot of money off of this as well and a lot of it through merchandising.

Toho has a much greater say on these movies than they did in 1998. They also want to/know how to make money. If they can liscence their creations in it they absolutely will.

Plus, I'm 90% sure the rumors of Legendary buying four other monster rights before Godzilla '14 started shooting. Good troll bait though, JetJagaSushiMan.