The internet is interesting because of the vast amount of information but also because it is visual. Many companies and developers have in house graphic designers but many do not. Those that do not rely on stock photography from sources like iStock and BigStockPhotos. Stock photo sources get photos from professional and amature photographers. If you have interesting photos, even edited photos, companies will pay you to use them either one time or everytime the photo is downloaded. 

You can now sell your photos in a new way called Non-fungible tokens (NFT). NFTs leverage blockchain technology simliar to bitcoin and other crypto currencies. Your photos are "minted" on a network such as the ethereum network. Once minted the NFT can be listed for sale and transfered to others. Many NFTs are edited and artistic (photo above is an example). NFTs can be minted manually on a blockchain but since most people do not know what that means there are various websites such as Mintable that makes minting, listing, selling, and buying NFTs easy. Payments for NFTs are in crypto (normally Ethereum) which means that the value could increase dramatically based on the market. Some have become instantly wealthy from their NFT sales.