Not sure what you mean here. I have two debit cards and my AMEX added to google wallet. I also have the GW physical card to swipe at stores like target and home depot where I will not use my other cards. Adding money to the GW card balance takes seconds. My wife and I both have one. I can even reload the card from my iPhone which has the Google wallet app.
I got it because I have used GW for years and she got one because her debit card number was used at Academy Sports and I was notified after the first debit (I have email notification) and by the time I could talk to a live person at Chase there were 5 transactions. Of course they covered them all but with Google wallet card they can only use what you have on it and you can freeze or cancel it instantly from your phone app and of course you get noticed with each transaction.
I will be interested to see what Samsung pay brings once it launches.