> In the first months, working with a realtor, we never saw a house not listed on MLS

I'm living in a house that wasn't on MLS when our "buyers realtor" showed it to us. (We were looking at another house and asked the realtor to get us in this one.)Unfortunately, we weren't able to stop it from being listed, so we had competition when we bought it, but .... Yes, this is highly unusual, but since we're trading anecdotes.

> Second we we're always able to call a sellers agent and get a showing.

If the seller involves a realtor, the commission is due in almost all cases, so buyers don't get to make the "realtor or not" choice.