Online platform is like the Arrakis desert

I've played the physical game for a while, and last week I finally bought the digital version. I've logged in several times since then and still haven't played a single online match.

The lobby is deep desert. Almost nobody is online, and the few people who are all seem to be playing with the expansion, which I don't have. So I sit there like a Fremen at the edge of the sand, thumping for a worm that never comes and rationing my patience like water.

Am I logging in at the wrong hours, or is buying the expansion the only real way to find a game? Right now I've paid for a harvester and there's no spice anywhere.