Its worth if you can use the voucher they are providing as per region. I recently used it in mysore, these are the benefits i got from 4k accor plus membership, booked two rooms for two days on my name, for one room used the accor plus mysore voucher for two days.
1. Got 4 drinks voucher. Used it for wine, gin etc. This would easily be 2k in revenue
2. Got late checkout at 2 pm.
3. Got chocolates since i was silver.
4. Got free buffet for two people which is 1998+ taxes in revenue
5. Used stay voucher for 6k which would be 12k in revenue
So just by one stay my membership cost is already recovered. Burnt around 13k points during checkout.
So membership is completely worth it.