Depending on the financial institution, that sort of app function would be outsourced to a third party anyhow. Payment networks are semi-separate from banks/financial institutions, and they're generally involved in digital wallets. And those payment networks are separate -- like how we recently saw the big banks sell Moneris, a payment network, off to US private equity. Or how Interac isn't a 'bank'. Even something like an ATM is a partnership between banks and payment networks -- you can see the payment networks ATMs are a part of on the decals on the ATM, which generally need to match the decals on your card. Those are the payment networks the banks semi-outsourced / partnered with for facilitating ATM activities. The bank buys/owns the ATM (typically), and then has an agreement in place with those networks in regards to payments / transactions, and a defined data exchange between those networks and the banks systems for settlements.

Migrations to google wallet are generally cheaper than getting that sort of feature with one of the older style payment networks, you're right about that. Cheaper by a fairly large margin.

One point I was making though, is that there are likely more companies 'seeing' the details of your purchase than you may realize. And many of those companies have significant ties to the USA, and are reliant on USA products/services. Even "local community credit unions" tend to use one of two networks, one of which has all its support coming out of the USA. Our government / regulators have made no movement to detangle any of that, and are, in fact, pushing more and more of your financial industry into offshoring services to the USA. Our government/Carney are all "Elbows up!" in the media, but "Pants Down!" in practice.