Why is Tundum and Dradoc.com linked to Apple Apps? (Zip)

Like others on this site, I innocently (and trusting) download Zip App from Apple, only to linked to Tundum and now Dradoc.com, billing my credit card (first $54.51 and then $2.67 minutes latter). It's supposed to be free so when it asked for my credit card I should have clued in. Tundum emailed me to say after my free access lasts only 5 days. My question, since both sites are obviously scams, why hasn't Apple blocked these companies? Will not be using Apple apps in the future.