AFT to receive incentive

Can we require a AFT in order for a customer to receive an incentive? We would like to add a $10 incentive if a customer setup a AFT transfer from checking to Christmas savings account.

AFT = Automatic Funds Transfer?

Reg E prohibits compulsory use 1005.10(e) where an EFT is required as a condition of a loan, and the bank may not require an account and EFT for employment or government benefits. It says nothing of incentive programs. Since the accounts are required to get the incentive, I'd say it must be OK.