True, but for some players, the position matters. If he wants to play CF, and there are similar offers out there (maybe just a bit lower, for example) from teams that will play him at CF, then it might require an overpay to get him. The Jays may have to really separate themselves from the next highest bidders in order to get him IF position matters to him (and I don't know whether it does or not).
He'd be smart to move to LF or RF, it should improve his defence in theory, but whether he wants to is a different story. An extra year would surely seal the deal, but no way I want Fowler on a five year deal.