Indeed. I was with a XS flight today from BOG to MDE and was given free baggage for 23 kg.

At check-in, I was speaking Spanish and English and the check in agent asked if I had paid for the baggage, and I responded it's included. She said "Oh yes yes yes." Then the baggage were checked through.

I did not bring a carry-on whilst check-in. But the staff indeed asked me if I had paid for the carry-on and I said I have a star alliance gold and she let me on.