In all honesty, we settled on those for manufacturing cost reasons. The original TS1 thermostat had a metal bracket that would mount to the wall and then the thermostat would snap into it. As part of the circuit board redesign for the TS2 we also looked into other areas for improvements and cost savings, one of the areas was how the thermostat was mounted to the wall. We were never huge fans of the dog ears on the side of the thermostat, but we needed to get part counts down, the use of the integral mounting ears saved a number of time consuming (thus costly) manufacturing steps, and they allowed for a flush mounting to the wall which was a complaint with the original bracket system. We ran the idea by a few stove makers and customers and got a more or less neutral response so we ended up going with it.
This along with how the cable comes into the thermostat and many other ideas are all on our radar as areas and ideas for improvement.