Google have been absolutely useless when it comes to marketing Wallet.
It works great. It's been out there for years now.
But have you ever seen an ad on TV for it? Have you seen ads online for it? Have you ever read an article about NFC payments that didn't talk almost exclusively about Apple Pay?
Google seem to think that as long as they put the tech into phones people will just somehow discover it, go through the pain of setting it up without really understanding how it works or the benefits of it, and trust loading it up with cash even though they've never really heard of it.
Seriously Google, your marketing people are failing you really badly here.