Because many Accor members reside and stay outside Europe, therefore, when the hotel converts your 40 euro voucher according to the hotel's exchange rate for hard cash currency exchange, you lose at least 8% and sometimes as much as 12%. Accor should really have a policy on hotel's using a certain Forex rate for this across all hotels. Anyway, use your vouchers in the Euro zone then it's 40 Euros. By the way, I don't find earning Accor points to be good for subscribing to the Economist. Usually you can get a better deal with promotional Air Miles - I've had Asia miles in the past.