I made a stack of them for the Farmers Branch Service Center. Chet did me a favor, so I made him some. It's not a pouch, per se, but a rounded black glossy vinyl square that has ~ .5" of overlap over the thin tolltag. You can stick the tolltag on the middle of the sticky part, then put the whole thing on the glass (or roof above the glass). Where mine sits now, next to the rain sensor, you have to look closely to see it. It's been there for over a year, and the tip of the wiper blade hits about 50% of it, causing no damage. The trick to making sure there are no bubbles is to spray it with lightly soapy water, then squeegee out the water/bubbles. As for theft, the location of mine up top would make someone have to climb up on the car to get to it. I haven't peeled mine off to see if it destroys it, though. I would think the risk of theft is about the same or less than the big black plastic thing on the license plate that says "This is a toll tag".
And for what it's worth, this tag patch was developed after I worked with an NTTA manager at the toll tag store, and many trips back and forth on the same stretch of Dallas North Tollway. The nosecone on my Dec 13 car would not allow the thin tag, thick tag, or the license plate tag to work. There are no places behind the glass that work, either. The tag's antenna is positioned on the angle of the glass to match the angle of the transceivers that NTTA and others use. If you stray from that antenna angle too much, it has a much harder time working.