I think a better distinction is 'paying customers' and 'non-paying customers'. Customers being a subset of users after all makes it a bit ambiguous.

Not that it should matter in the context of the feature being described.

I'm still not a native English speaker, but a Google search shows that non-paying customers are people who don't pay their bills, which is not the same thing as users who don't have bills to pay.

Also as I wrote, Zoom was thinking of selling E2E encryption as a payed feature, that's why the distinction really matters (I would happily pay for it if that would give me a strong assurance that I just don't have so far).

I don't think I'd happily pay for Zoom, regardless of their encryption promises. I've personally struggled more with zoom call quality issues and hardware conflicts than I have with any other video conference provider.

Also anecdotally, I hear the opposite from every single person I know. Zoom has been the video conferencing system that works the best. Have you ever used Go2Meeting, WebEx, Teams? Constant struggles with those applications for me, my friends, and my co-workers.

You really have to use Teams every day to appreciate just how buggy it is on all three platforms. I used slack video for remote standups for a year or so and aside from the odd little hiccup it was boringly stable. Teams fails at least once a week.

In my experience, Google Meet is the one where no-one has problems. Zoom and Teams are the least reliable of the bunch.

Non-paying customers can mean either customers who are delinquent in paying their bills, or customers that are using the service for free with permission.

Non-revenue customers for the latter (from airlines)

What's the difference? Aren't they the same group of people in this context?

I'm sorry, I'm not a native English speaker. According to the Oxford dictionary customers are people who buy a product or service.

Zoom was thinking of giving only them E2E encryption, and actually I would pay for that service if I would trust Zoom. Currently I use telegram to speak with my friends, but the call drops quite often as we don't have stable internet connection.

Maybe, since you admit your English language skills could use some work, you should give up on linguistic pedantry and find a new hobby.

If my English here is so bad why do I see ,,end user'' in Zoom's terms of license all the time, and customer for paying customers?

Can you provide a better legal definition than what I see? (Only the legal meaning of the word matters in the current context).

We're talking about hundreds of millions of people being effected vs few million people, it matters a lot. You would understand that it's very far from pedantry if you followed all announcements that Zoom had in the past.

Free users are not customers.

Only drug dealers and tech call their customers -users-

haha yes, true.

Which explains why UI's generally are about as pleasant as scoring a dime bag on a dark corner.