PuRe

you need a receipt from some sort of shop saying the work was performed.

I recall several instances where people were able to prove their case with receipts from third party garages. Unfortunatley, the onus is on the owner...and AoA is pretty strict.

High Launch Low Spin

Extract the old oil at 5K. Don't change the oil filter. Get the Mobil 1 synthetic oil from Wally World. When your ride is ready for the 10K oil change bring it to the dealer. That way you don't have to save receipts for oil changes and AOA can't deny the warranty because according to their records they've done all the oil changes.

IIRC $60 for oil extractor, $15 for Mobil 1, and AoA cannot deny warranty = priceless.

PlainRuss

You'd be amazed at what some people will do. I know of a few people that would go 20,000 or more miles and not bring their cars in for their free maintance, and then wonder why their engine is not covered. People will make up bogus receipts, etc. In reality, a handfull of receipts from the parts store for oil and filters proves nothing. I could collect a bunch from receipts from my neighbors cars and that wouldn't prove anything. When you go to a shop, it shows the car, the date, the miles, etc. Puts me in a crappy spot as I have paid anyone to change my oil ever, and I am not about to start now. But if I don't have documentation and something happens.....I'm screwed.