WETH is used to make bid offers for NFTs on OpenSea, which is currently the largest NFT marketplace. Additionally, looksrare.org is also a popular NFT marketplace that uses WETH. Bid offers on these platforms are made with WETH instead of ETH. So, if you’re looking to buy NFTs and you’re holding ETH, you most likely need to convert them to WETH before you’re able to make any bids.