A Redditor took his cat and dog in for a checkup, and convinced the vet to accept bitcoin payment:
"Was there with my cat and dog for a checkup, talked to him about it ... he didn't have time to listen right now. He heard about it before but doesn't know a lot about it. I asked him to call me later if he's interested.
And then when I got to pay I asked if I can make this one payment with Bitcoin ... and he said "sure, why not".
So I opened a blockchain.info wallet for him, and paid. So much fun."