Erm, the routes I'm talking about are internal Chilean flights like the one mentioned in my previous post, terminating in La Paz, Bolivia. All LAN Express flights are one-class. You will have found that the EZE flight was two-class because it's a mainline LAN (International) flight. When I flew down to PUQ, I too saw a two-class config, but understand this to be a rarity.

To clarify, my point was probably more geared to those who travel on LAN using RTW tickets, as the rules of these state that A and D class tickets will be booked in Y class for domestic routes.

All info is based on first-hand experience as recently as last week.