Instead of using a golf tag on the putter, it might really useful for some people to have a golf tag with no spike on it, and use it as a ball marker on the green. This way you could scan it just before you mark your ball each time. May be an additional feature to be included in future sets of golf tags.
I order my tags through the kickstarter campaign they just ran. They come with 15 tags and that is what I plan to do with my "putter", I'm not sure if I will shave off the screw part yet or not. I have a grip on my putter that has a magnetic ball marker and no hole to screw into.
Just a bump... I think this would be an incredible add-on to the golf tags. I often forget to scan my putter with everything going on, on the green...but like to know where I hit it to. A nice well made ball marker, golf tag would be really cool/