I just don't think that "seeing what is included in a airline ticket" is all that complicated, or that it is simpler somehow than deciding on, administrating, and enforcing a "standard bundle" on all these different airlines. And there's nothing to say that the standard bundle will necessarily meet that many people's preferences. I mean, people distinguish between different services and goods all the time depending on how much they value them - I don't think they suddenly lose this ability when comparing flights.