Should parents and adult kids living on their own have joint bank and financial accounts?

Interesting wrinkle with our 529 (Vanguard) which only allows electronic transfers to the owner’s bank account (payments to a beneficiary have to be done with a check sent by mail). So I’ve stayed listed as a joint owner on the kids’ bank accounts while they are in college since they pay the tuition bills, apartment lease etc with 529 withdrawals and I don’t want the risk of a check going missing or the delay of multiple transfers (also the 1099-Q lists me as the recipient).