It's built in to Siri though. So Apple benefitted from Shazam. I'd say Apple's Weather app has also significantly benefitted (albeit a bit late) from Dark Sky's acquisition
Filemaker might as well have been bought when dinosaurs roamed the Earth. It's such an acquisition from another era that it's a fully owned-subsidiary of Apple inc. that is completely separate from the rest of the company. Do you know how many other subsidiaries Apple has?
It (optionally) integrates with the Apple Music Android app now, and offers to add to your library there whenever you scan a song, so I assume it's a good funnel for them to get people into their service ecosystem.