A cake, a waived meal and store credit are different benefits. Understand what you need to pay first.
Spending now versus spending before
No purchase at redemption can still require an earned membership tier. An unstated restriction is unknown, not proof that there is none.
Count paying companions carefully
A party of four and four paying adults are different. Check whether the birthday guest and children count toward the requirement.
Credit is not cash
Vouchers and store credit can have minimum spending, product restrictions and expiry dates. Compare your actual bill, rather than the advertised face value.