I imagine that happens a lot, although that wasn't the case for me.

And actually, they handled the cancellation process well (at least for me).

I called them up and said I want to cancel because "their site is a scam" and in a no-nonsense way the person started helping me undo the payment (without defending the site). Since I paid through PayPal, I did have to dispute the payment via them (which took a month or two) but I eventually got all of my money back.

So I give the company (or at least the person I talked with) props for their cancellation process, although not everyone may experience it that way.