http://www.coindesk.com/does-google-wallets-slow-adoption-bode-badly-for-bitcoin/In May, Google announced to its merchant partners that it would be retiring Checkout. Google Checkout was designed as a platform for online payments, but as a competitor to PayPal it wasnt getting enough traction. The companys plan is to merge Checkout into Google Wallet. The idea always has been for Wallet to be via Android a replacement, well, for your physical wallet.
Credit cards have become so ubiquitous, it is hard to get people to change a habit. Particularly if they don't see an immediate benefit but do see an immediate hassle to setting it up.