But at least the book clubs (at least the ones that I know) make it obvious that you sign up for a membership and have to buy something (monthly or yearly).

This site seems to be entirely designed to mislead you into thinking you're just ordering one item, while in fact you are signing up for a membership.

Signing up for the first one (book club) may be a bad business decision on the customers part, but this second style simply seems fraudulent to me.