I've edited my initial reply because I was going off the 1.5c per payrewards point (3c per QFF) calc but I don't think that's accurate, the public rate on their site is 1.8% for 2 payrewards points per dollar (effectively a 1.8c acquisition rate for QFF)
Sounds like your offer was 1.5c per QFF point? That can work, it's not out of the question, especially if it's for business expenses and potentially tax deductible. But you could also get 1.5cpp through other means. I'd only consider it for business expenses, personally.
If your offer is to buy at the 1.8c published pay.com.au rate and especially if it requires some sort of subscription on top, I'd be walking away