Why did I pay 8.7% in miner fees? Yesterday I did my first Bitcoin transaction for something physical. I bought a couple of drinks at a pub.

I was shown a QR code which I scanned with my Blockchain.info iPhone app. What caught my eye in the transaction were the miner fees of 0.5 mBTC / 5.7 mBTC = 8.7% (much larger than the 2-4% fee for credit cards).

Is it standard to pay such high miner fees for physical items to expedite confirmation? Did the QR code dictate the miner fee I had to pay, or was it the iPhone app?
It was the suggested fee that your app set, I believe you can also customize fee size on most apps, but the suggested fee is for confirming the transaction ASAP. I believe POS stuff like that doesn't really care for confirmation time so you can safely set a lower fee.