Well a simpler way, if people know iPhone/ipad is to use Siri. You can push the home button to access Siri & ask, What's my name. When I just did that on my locked iPad it showed my name & email. Can't remember if it showed my phone #.
But it looks like otherwise, Find my iPhone/iPad is rather useless to find the device, except for ones w cellular.
I left my iPad in my car last night (locked) & didn't realize it until rather late. When I couldn't find it inside, I figured it was probably in the car. Tried find my iPad but it showed offline. So, as others said, in most cases if it was left some place it would be offline--unless we had accessed wifi there.
So maybe we should make it a point of accessing wifi at places we might have our iPad even if we don't actually need to use wifi there. But I guess I have logged into wifi at various places such as my office, church, Starbucks & Burgerville & some other places.
But I've noticed that it seems like it may lose that when iOS is upgraded.