Re: A bit too convenient
I really don't think they've thought this one through very well! There's bound to be some kind of issues with anything that can be read and authorised without contact.
I would prefer an e-purse on my debit card, so I could maybe pre-load it at an ATM with a fixed amount and treat it like cash. I don't like the idea of a NFC system without pins being able to dip into my bank accounts / credit card accounts.
We have those toll tag systems here in Ireland too, but they're a bit more comprehensive than just toll payments. They setup a whole clearing system so there are multiple toll-tag operators and you can use them to pay for barrier-free tolling on some tolled roads. They're just read from transponders mounted on gantries over the motorway. You don't even have to slow down for these as there are no barriers at all.
You can also use them for the express-lanes or any other lane of toll roads which have barriers.
They've extended the functionality though and they now also work for payments for quite a few car parks. So, you just drive in the tag's recognised and the barrier lifts. Then when you drive out your payment is collected via the RFID tag on the window and it's debited from your bank account / credit card or whatever you've setup.
There's no risk of scamming it as you'd have to have access to the clearing system to get payment so it's just a few toll operators and car park operators. However, for these NFC credit/debit cards, there'll be far less control as there are millions of retailers and card processors out there.
BTW for US readers - here in Europe, Chip and PIN credit/debit cards are the norm. You have to insert your card into a reader and key in a PIN to process a normal transaction. Swipe / Swipe and Sign systems were phased out of use as Smart Cards and PINs were considered more secure.
This NFC system just undermines all that!