What do you expect from Facebook? They make their money with advertising, of course they will exploit and capitalize everything that gets send through their channels.
Neither WhatsApp nor Facebook can read your messages or hear your calls with your friends, family, and co-workers on WhatsApp. Whatever you share, it stays between you. That’s because your personal messages are protected by end-to-end encryption. We will never weaken this security and we clearly label each chat so you know our commitment.