Double-edged sword
Technology like the RFID cards can be used for many purposes, both good and bad.
From the organisers perspective, using the RFID tag as a payment method reduces the amount of cash on site, so it will probably reduce some of the petty theft that happens at these events. This will benefit the customers, the people who run the concessions (they don't need to maintain cash floats), the organisers (who don't need to have cash handling facilities for the concession operators), and the Police who will probably see a reduced number of theft reports, especially if the RFID has a second factor (PIN?) to authorise payment.
It also makes sure that people only have access to what they have paid for, making it more likely that people at the festival actually pay the right price to see what they want.
Tracking people who move around is something completely different. While it will happen as a side effect of the entitlement checking, it's no different to having a barcode on a ticket, which is frequently used at attractions.
The only time it may be intrusive is if they have silent, unmarked RFID scanners scattered throughout the event, not just at the gates.
I think if I was there (which is not going to happen, partly because of these concerns), I would probably want to take a foil-lined pouch or tin to keep the tag in (depending on whether it is a wrist-band or a dog-tag, both terms are used in the article), and only take it out when it is necessary.
I don't really agree with facial recognition, but as that can be applied both in real time and in retrospect to captured CCTV video, there's not really much point in objecting to that, because it will happen anyway.
It's not that I'm paranoid (well, not that much), rather than I object to the concept of there being the ability to track me.