Truly paranoids are/will/should use Bitcoin or Litecoin. I don't get why pricing is USD$ only, it just seems that cryptocurrencies are perfect for this kind of service.
If your opponent uses geographic profiling, you want to pick a point far away from you and then go to stores far away from that point -- then they'll identify that far-away point as being your origin. If your opponent is a game theoretician, on the other hand, you want to pick stores to visit completely at random, in order to avoid providing any information.
Coinbase comes close -- the only thing they don't do is allow me to specify at run-time how many USD I want; for some odd reason they need you to "create a button" with an API call before displaying that button on your site, which is a pain to deal with when you have variable payment amounts.
Not leaking metadata on credit card statements that allows to infer that valuable data is stored at Tarsnap (and approximately how much), would be a practical increase in security: Such a leak might prompt an attacker to allocate more resources towards compromising the Tarsnap user's client computer.