For instance, it could instruct specific clients to encrypt and send each message twice: one for the recipient, and one for the WhatsApp server. As long as this was off for 99.9% of users, it's unlikely that security researchers would ever detect this.
Especially as ESL are usually kept secret within the company, this would be too risky, developers would ultimately find such a backdoor (especially since it generates a lot of server traffic).
I can't think of a company I trust less than Facebook.
I can use cash at Walmart
Never heard of Glencore or Phillip Morris.
As for Blackwater and Palantir, my impression from the media is they do exactly what they say. It's not like Palantir lies about harvesting data to give to government. I trust that they actually do do that.
None of those companies have posted fake news and altered the news algo with the express intent of manipulating users' mental states for reasons that basically boil down to "for the lols" and "let's see if we can make money from this".
The amount of passion in your comment and this gap in knowledge don't go well with each other. I encourage you to at least read about Philip Morris (or watch John Oliver's episode about them at least).