True, last minute trips are often not available for 25K miles - but the only time I needed to go somewhere the next day, my primary airline, AA ,had plenty of availability. It ended up I needed to change my travel date too and it was great to be able to change my ticket (most award tickets are changable - but airlines often charge a change fee now). In my opinion if one acumulates miles on several airline, one is unlikely to be unable to get a last minute award seat on a route several airline fly. For example, I have miles on AA, UA, and DL I could also use my miles on AS, US, NW, and CO. Chances are I could get a last minute seat (assuming I don't need specific flights).