Free night vouchers can indeed be very tricky to redeem at some properties. Still, a lot of very nice properties readily accept the vouchers, like the two Sofitels in Bangkok, Sofitel Macau. I even managed to use the free night voucher at the Pullman Danang Beach Resort during very high occupancy in mid August, where nightly rate was north of US$ 200 for the basic room.

OP sounded very sour in her post. I suppose she had different expectations altogether of the program. I have been very happy being Accor Plus member. I'd say the 10% savings of all bookings is the main deal for the package for me.