Can someone tell me the attraction of that feature? Is there a practical use, or is it just kind of a self satisfaction thing? (scratching head)
Sure... the premise (which works with other sites) is that when you approach a station (or a store or restaurant), your appropriate data will automatically appear. For e.g., if you come to a restaurant and have a credit with that place, or a reservation, it will automatically appear and be functional when you enter the restaurant.
In theory when you entered an Amtrak station, if you had a reservation, your reservation would automatically appear and be "scan-able" by the conductor.
Great theory... but it has not worked well with Amtrak. Alas.