Yes. It's extremely predatory. I commonly see people asking for financial support when they have gone way over their ability to pay back. In Australia the fees for late or failed payment are often starting at $10 per instance.

I used a similar service once to buy a plane ticket, which was very sudden and unexpected, one week before I got paid (monthly). Even though I knew I had the remaining payments coming up and budgeted for it, the psychology of having the cash in your account absolutely can tip you into buying more before your last purchase is paid off.