FORTUNE — For a few weeks last month, it seemed clear enough: Facebook (FB) would acquire the long-range solar-powered drone maker Titan Aerospace and use its technology to deliver Internet to remote areas of the world. It was ostensibly a hedge against Google’s balloon-driven Project Loon and the possibility that Google (GOOG), rather than Facebook, would connect the “next billion” Internet users.

Today that picture is opaque at best. Google — not Facebook — is buying Titan Aerospace, and Facebook has acquired a different U.K.-based solar-powered drones startup called Ascenta. And an answer to the question of how exactly the two Silicon Valley giants will leverage their new technology? Still elusive. What is clear is that while delivering connectivity to far-flung parts of the globe is advantageous for both Facebook and Google, the race to acquire unmanned aerial systems, or UAS, technology is about much more.

Exactly what, well, that’s more difficult to discern.

“You definitely have to look at it as part of a broader business strategy,” says Mark Bünger, research director at Lux Research. “The two of them are shooting for the strategic high ground here — Amazon is obviously doing this, too. I think they have a lot of ideas for what it’s going to be important for, but I think right now anyone would have a hard time accurately saying what that’s going to be. In other words, they don’t know exactly what it’s going to be for, they just know that it’s important that they’re there.”

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For Facebook, the incentive is simple: catch up. Rival Google has been developing a means to provide Internet connectivity to remote regions of the world for years now through Project Loon, which uses Internet hubs suspended from high-flying balloons to provide bandwidth to areas of New Zealand that are off the wired grid. Facebook isn’t breaking new ground by getting into commercialized drone technology, Bünger says, just keeping up.

“Google has been working on the autonomous vehicles, the Nest acquisition, and a bunch of other stuff that’s surprising if you think of them as a search engine company — which hopefully nobody does anymore,” Bünger says. Facebook knows that if it wants to remain a major presence in the emerging Internet of things, it will need to extend beyond software and into hardware. Drones are one means of doing so.

UAS are also a means of bypassing mobile carriers, which have given Facebook some trouble in parts of the developing world, particularly where the company has attempted to negotiate “zero-rate” deals that allow customers to use some of Facebook’s offerings without it counting against their data plans. If Facebook does follow through with its ambitious plans to connect the next billion people through Facebook-owned Internet drones, Facebook can not only bypass mobile carriers that don’t want to play ball, but also push those new users toward Facebook offerings like its recently acquired messaging app What’sApp.

But one oft-overlooked area where UAS technology could really be a boon for Facebook is in data moving the other direction. Right now, Facebook owns mountains of data on its users, but relatively little on the parts of the world that aren’t already connected to Facebook. Comparatively, Google’s acquisitions and exclusive deals with third parties provide it with everything from the rich trove of geospatial data that powers Google Maps to the energy use and living habits of those using its Nest smart home technology, providing a far more robust picture of the world and a wider range of services it can provide. 

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With a fleet of UAS in the sky, Facebook could begin gathering its own proprietary geospatial data, aerial imagery, traffic data, meteorological data — information that it could then integrate into new products or sell to companies that need it, much like Google does and other companies threaten to do, at least with regard to drones.

“For Facebook and Google and those guys, they know they need a toehold in this space,” Bünger says. “There are a hundred other areas like that where they’re having to compete now to get a toehold in the technology, and they can’t really know right now what they’re going to use it for. Nobody really knows.”

At $20 million, Facebook found its way into the drone space for a third of what it was reportedly going to pay to acquire Titan. The terms of Google’s purchase of Titan haven’t yet been disclosed, but whatever the final figure, it will likely be worth it. The acquisitions certainly have the attention of the rest of the drone industry, which now largely consists of small, privately held companies sitting on various competing technologies that are waiting to see how customers — or perhaps future corporate overlords — will put them to work.

With the FAA and other civil aviation authorities moving toward policies that allow for the commercial operation of drones in civilian airspace, it seems a foregone conclusion at this point that more drone technology acquisitions are in the offing, Bünger says. They’re not just vanity projects, but necessary pieces of a competitive technology portfolio.

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“For these companies these are very well-placed strategic bets,” Bünger says of the recent acquisitions. “I don’t know why in the world WhatsApp was valued the way it was, I can’t even imagine. But these things — Oculus Rift; both of these drone acquisitions by Facebook and Google; a lot of this technology that has to do with wearables; autonomous robotic systems on land, sea, and air; technologies that have to do with crunching all the data that you get from all these things — those are the weapons you need to have with you going into the next competitive battles.”