Too Long; Didn't Read
With a good algorithm, you can simultaneously solve several problems associated with smart contracts that work with large lists of user addresses. You can’t add a list of several thousand addresses to a contract and allow this set of addresses to do something in that contract. The <a href="https://hackernoon.com/tagged/blockchain" target="_blank">blockchain</a> tries to save every single byte, so it would be too expensive to have so much data there.