Their active area is so small that an ordinary USB-A power outlet would be more useful. You have to plug the rigid coil into your device, then place it exactly over the charging circle.

Induction is a very practical solution for when you don't have your USB charging cable with you. Plus, who's going to steal the coil to use at home? And it's a pretty magical experience when you use it.

That your phone can get position info from satellites is magical. That you can bring two halves of a transformer together and get power would not have surprised an electrician from a century ago.

> You have to plug the rigid coil into your device,

What is the point then? Plug in your phone, so you don't have to plug in your phone?

The problem is that Starbucks uses Powermat pads which are incompatible with Qi in most smartphones. Powermat has most public locations while the Galaxy S6 is the first, maybe only, phone that supports both Qi and PMA.