I've been an Accor ALL Platinum for a number of years, and can confirm that the recognition/upgrades/gifts etc can very considerably, and unexpectedly. I'm not greatly fussed by a couple of chocolates or pieces of fruit, and the welcoming drink can range from something very minimal to a choice of anything I'd like from the bar.
I've got a freebie Accor name tag on my backpack, which was spotted by a passing hotel executive in Canberra, then followed by a very speedy queue jump and check-in process. I've had amazing room upgrades in Singapore, the UK and Europe, but also nothing at many Australian locations. Sadly, I've found it's some of the Australian country locations that are the most disappointing.