Should we really be paranoid?
So I went to wikipedia.
The examples and perspective in this article may not represent a worldwide view of the subject.
Contactless payment systems are credit cards and debit cards, key fobs, smart cards or other devices, including smartphones and other mobile devices, ...
Mobil was one of the most notable early adopters of this technology, and offered their "Speedpass" contactless payment system for participating Mobil gas stations as early as 1997.
Remember that opening statement from wikipedia: "The examples and perspective in this article may not represent a worldwide view of the subject."
Here are some valid concerns but it's from the UK.
Here is a North American-centric view of contactless payment systems.
"Nothing to see here, move along".
But remember that wikipedia also said: "...including smartphones and other mobile devices."
But smartphones and other mobile devices won't fit in the little case.
Not to worry.
Although these are "contactless" they are based on NFC. Although NFC is contactless there is always another layer of security, e.g. TouchID for Apple Pay.