It’s difficult to get a good looking compromise with transitions.
Sunglasses lenses tend to be pretty enormous in comparision with glasses lenses, and the frames tend to be much thicker, with thicker arms. So you end up either having massive glasses which look OK when tinted, or normal sized glasses that look tiny when tinted.
Even “big” glasses are relatively small at the side of a pair of sunglasses.
Chuck in that there’s less need for high index in a thick pair of frames, little need for MAR etc. meaning you can pick up prescription sunnies online for very little. I’ve got a pair prescription Raybans here that cost less than retail for a normal plano pair…