Maybe because its a program designed to reward loyalty? Or because many properties choose to recognize customer loyalty by upgrading to available executive room? Actually I don't care about the room, but lounge access is big for me.

If Hilton's response is the same as some of some responses in the thread -- if you want an Executive Room then pay for one -- that means I will not be loyal and choose a hotel based upon price and amenities and not the loyalty Hilton and other chains so heavily promote. That means Hilton may lose some of my business as they lost the business of the OP.

If Hilton wants to leave better rooms/amenities unused rather than allow a loyal customer enjoy them then it does not give me an incentive to choose Hilton.