Penn students receive course credit for participation when they are recruited through the SONA system.
We get cash at the bank with our lab's debit card (via the ClinCard method).
We pre-load our Prolific account $1k at a time with a ProCard.
Amazon gift cards are for occasional use, when paying someone cash is not possible (e.g. our cash ran out that day or we need to mail a payment)
We pay $100 a week to aftercare programs. Penn allows us to consider this subject fees, so we use the ClinCard method to provide these payments.