But why whitelisting? Don't understand the need.
Hello, coindoctor! Thanks for asking.
The idea is to offer guaranteed participation for our supporters without the need to rush, spend a lot of gas or anything like that.
If someone hears about the project today and join the whitelist, when the sale starts this person will have 72 hours to remember to send his/her contribution.
If our token sale smart contract only limited 10 ETH per different addresses (with no whitelist), one of the things that could happen is that if the sale starts really well some people could decide to create multiple wallets and raise their investment size, and people that are supporting us since the beginning and small investors could be left out.
By creating a whitelist, we make it harder for people to create multiple accounts, we guarantee participation for everyone interested and we can keep track of the number of people subscribing every day. This model was successfully used by other ICOs, such as the 0x Project.