But with the $1000 per ten day limit at the mint, it would mean holding onto a lot of coins to accumulate enough to make the tuition payment. You'd miss out on the opportunity cost of that money (at minimum, the 1.5% interest you could get at an FDIC insured money market account).

Yeah, I know there are ways around the mint ordering limits, but even so, you can't come up with $60k without some lead time, and that would incur holding cost.