Sprint "Touch" is not only expected to challenge Google Wallet, but also ISIS, which is the work of three of the top U.S. carriers. Obviously, Sprint's mobile payment system is a real threat to Google and it seemed more than a coincidence that the Google Wallet wasn't playing nice with the new Sprint flagship smartphone.
A Google spokesman has informed The Verge that the HTC EVO 4G LTE's inability to access Google Wallet is due to a "software problem" with the NFC component on the phone that could be fixed with a software update. HTC, Google and Sprint are said to be all working together on the update which is said to be coming soon.
source: TheVerge via AndroidCentral