With the growing popularity of smart contracts, there is a high price associated with getting a smart contract audit. I was wondering if a pre-ICO would require a smart contract? Or should the tokens be generated first then during the ICO, all whitelisted address would receive their tokens including those from the pre-ICO. Thank you for your constructive responses.
With the growing popularity of smart contracts, there is an even higher price associated with broken smart contracts getting drained for millions of ether due to poor implementation.
With that being said, no one is forcing anyone to do their pre-ICO through a smart contract, however, it is a convenient way to do it and it harmonises well if the subject of matter is going to carry out an ICO eventually anyway.
Usually for pre-ICO's, tokens are generated in the same fashion as for the ICO, however they are not made transferable till the ICO is complete or the project is listed on an exchange.
No ICO needs a smart contract, it can all be done in a centralized way. You basically answered the question for yourself.