This is also why I prefer using credit over debit cards: with credit, a fraudulent transaction (before being cleared) is merely decreasing my available funds (and because I generally pay off my balance monthly, this has zero impact on my life). With debit, the money comes out of my account, and only once a fraud investigation is complete do I get my money back.

Contactless cards also typically have a per-transaction limit in the area of $100~$200, so the amount of damage someone can do without the PIN and before you cancel the card is quite limited. I actually wouldn't be surprised if you do too many transactions in a certain period of time it would ask you to do a PIN transaction.

Well, cards can be canceled and fraudulent payments reversed. The same can't be said of cash.