Maybe the boom will last another 3 years and new deals financed today will be able to go public and the investors will get to cash out after the IPO lock-up period ends.
Gift cards have a lot of benefits for small businesspeople who want to lock in future business with new customers, and get cash up front for future sales.
Position-traded money market funds are a different type of lock-up: Investors must place a trade to get into or out of the fund, which can take a day to complete.