Sex is mainly for procreation though many people use it for recreational purposes. Does it have another use.
Bitrefill: Bitrefill enables users to purchase gift cards using cryptocurrencies and also sell their unused gift cards for Bitcoin. While it's not exclusively for gaming vouchers, they do offer a range of gift card options, which could include gaming platforms.
eGifter: While not primarily a cryptocurrency exchange, eGifter allows users to buy gift cards using Bitcoin. This could include gaming vouchers for various platforms.