Amtrak Guest Rewards - AAA Adult fare > Regular Adult?

Under what circumstances can using the AAA discount increase the Adult fare?

I'm looking at #178 out of PHL to BBY on 08-OCT-09 and return on #67 BBY to PHL on 11-OCT-09. Individual segments price out at $60. RT regular Adult is $120. AAA Adult is $144!?

They're the exact same trains with the exact same Reserved Coach seats. Why would AAA have to pay more?

The base fare is $160. AAA gives you 10% off ($144), but the 14-day advance purchase discount gives you 25% off ($120). The two cannot be combined.

Be aware that the 25%-off "sale" advance purchase fares (which the online booking system defaults to selling you) are non-refundable (http://www.amtrak.com/servlet/ContentServer?pagename=Amtrak/am2Copy/Hot_Deals_Page&c=am2Copy&cid=1188834241656&ssid=224). So the one (questionable) advantage of "forcing" the online book system to use the regular, base fare by using the AAA discount is that, as I understand it, it makes the ticket a refundable one.

Although non-refundable, the value can still be used as a credit on Amtrak if you cancel.

One thing rather annoying about the web site is that it doesn't tell you if there's a fare cheaper than your "discounted" fare. It's also not possible to book a non-promotional fare if you don't have another discount to override it -- you want a refundable fare but aren't NARP or AAA.

Thanks, everyone. Wish the site was a little clearer regarding base fare & discounts applied on the "View Fare" confirmation page.