As a word of caution, it's not just Filipina's they ask to see the credit card you booked with. A few months ago I was flying with RBA from Manila to Bandar Seri Begawan, I'd booked the flight on line with RBA. The counter check in girl at NAIA asked to see the card I'd booked with. As it was a round trip back to MNL, she also asked to see a copy of my Cathay Pacific ticket out of The Philippines so that I couldn't break the 21 day rule. Fortunately I had everything in my hand baggage. The RBA check in girl did the same thing in Brunei when I was leaving there en route to the Philippines