But the airlines don't really give a crap, southwest started basically as an air bus, show up buy a ticket get on. No reservation, no id, nothing.

The airlines don't even check ID most of the time with these electronic boarding passes if your not checking luggage.

If you are flying domestically, the airline doesn’t care. They know that someone bought a ticket to get pass security and that ticket matched the ID of the person who got through security. They don’t lose money and thier is no increased safety risk.

They do check your ID for international flights