Wouldn't you still have to pay to keep it working, or the person who lost it could simply just shut it off?
I mean, brilliant you found that, really! Well done! But if I lost my phone, I certainly wouldn't keep paying for someone to pick it up and run about, using the bloody thing. Unless it's pay as one goes. Then you win at everything.
Did you spray it with lysol too? There could be germs in and around those keys, bwahaha!