FPs to bar is a disappointing move from InnoGames. The motivation is, according to rumor, that it improves the flow of FPs. It will obviously do that. The interest in "improving the flow" is presumably because it makes players more predictable, and easier to guide into the game functions that are the most profitable, or easiest to provide. That, however, is just another way of saying "it removes the players strategic options, reducing him/her to doing mindless tasks".
For a strategy game, that's not a viable long term, ahem, strategy. The main reason for playing strategy games is precisely the challenge of choosing the right option among many (preferably infinitely many). For some strategy games, FoE among them, rewards for delayed gratification is an essential part; one must plan far ahead, as few things give immediate results. That's what makes us long term players; we stay to see our plans pan out, the GBs starting to pay for themselves, the city we envisioned being realized. Meanwhile, of course, we make more plans, build more GBs, and envision further ahead.
One of the things we plan ahead, is the use of FPs. Using them in rapid FP swap, saving up for a building we're still collecting BPs for, saving so we can reach critical technologies quickly after crossing into a new age, keeping a few in case of unforeseen needs, etc.. Even "sniping" positions in GBs is a legitimate, if annoying, strategy. These are just off the top of my head. A significant number of strategic choices have been taken away, in order to make the players more predictable. Or, put another way, give them a more boring experience.
Edit: Amended an ambiguous phrase.