Eating vegetarian isn't entirely based on saving the planet/environmental issues. Think of it this way, if we could make it so eating meat had 0 environmental impact and eating vegetarian/vegan had 0 environmental impact would there still be major reasons to be vegetarian/vegan?
I'd say the main reasons for being vegetarian include not wanting to contribute to raising animals just to slaughter them, or eating other "living" beings and objecting to the conditions in which they are raised before they are slaughtered.
Paying extra for the Impossible brand name is mainly for those wanting to switch from meat yet still yearning for the texture/taste of meat. A brand like Impossible foods ensuring consistency across restaurants would contribute to people choosing to switch from meat knowing they are getting a product they have had (and enjoyed?) before.