As to why anyone would think of this as others have asked in other comments below? You don't see many pro-meat groups (are there any?) fire bombing vegetable stands but PETA, ALF and other extremist groups who are vegetarian due to their views on animals do use violence; verbal or physical to intimidate people.
Pro-meat groups, known as the agribusiness, grocery, and foodservice industries, torture and kill animals and flaunt the carcasses to the public. So there is that.
More seriously, what would the dominant normative side of an issue need to even consider terrorism, the status quo is already in their favor.
As to why anyone would think of this as others have asked in other comments below? You don't see many pro-meat groups (are there any?) fire bombing vegetable stands but PETA, ALF and other extremist groups who are vegetarian due to their views on animals do use violence; verbal or physical to intimidate people.