They certainly shud have informed you, though I think the August travel rush is in full swing, and is therefore mostly to blame.
Now when I travel in summer and have a hotel offered, I call the airline before I leave the room to ensure no delays.
Though it shud be the airline that take the proactive step in informing passengers, I think u can save urself some headache by the passenger contacting the airline instead.
try and go for the business class lunge instead. I think you can pay $20 and gain access.
good luck