There's a huge error in an otherwise good article about traveling by Amtrak on a long distance train:

"Also, economy does not include meals in the dining car and gets you no access to the observation car."

This is not true. Anyone on the train can sit in the observation car. Downstairs from the observation car is the snack bar, which was the only source of food for coach travelers when Covid otherwise closed the diner to non-sleeper passengers.

Source: I've ridden the Zephyr many times, the Southwest Chief is the same.