The ones I know of are not really masquerading, but rather, funding themselves and/or directly related services (often hosting) via convenient ways.
- Conversations.im (XMPP/Jabber client) is $8 on Google Play, free on F-Droid and is FOSS. Dev runs their own instance.
- OsmAnd+ costs money on Google Play, is free on F-Droid, provides hosting of gigabytes of map data.
- Beeper (bridges from popular chats to Matrix) costs money (subscription I believe), but can be set up on one's own (I run two bridges on my chat server).
What I do dislike is companies overusing "Open" or "Free" in their own or their product names, with no implication of Free or Open Source software. Similar to slapping "engineer" on non-engineering roles or "manager" on non-managerial ones.