Worst case scenario they will tell you what they think is right. But we all do that, it has nothing to do with meat. Hell, try to have a discussion about driving habits and you'll see everybody will tell you what to do.
Second, yeah, taxes are probably just motivated by money, and trying to get veggies to support it.
But even the worst detractors of the theory agree that more than 14% of green house gaz is animal agriculture (https://www.skepticalscience.com/how-much-meat-contribute-to...). Those numbers do not include transportation, wrapping, cow farts, water consumption, soil pollution, and exclude deforestation done for animal agriculture purpose.
So there is something here. There is no need to fight about this. However a sane debate seems in order.