It's really hard to call something "anti-competitive" when, at this point, they're only a theoretical competitor.
I think it's most likely that Apple just doesn't want to get associated with any of BitCoin's less savory associations; the next time a Silk Road-type operation gets taken down, they don't want to be part of the story, even peripherally. And, the Silk Road takedown's been getting a fair amount of mainstream press lately.
If Apple does come out with their own PayPay-type competitor, then of course they wouldn't want to facilitate the use of BitCoins, but it seems to me that's really a secondary concern at best. It's not like they're going to destroy BitCoin by kicking out these apps. Who's to say they've got any intrinsic right to be including on Apple's platform, anyway? If having a BitCoin wallet on your phone is an absolute requirement for users, that's just an incentive for them to buy an Android device.