The carnist here claims that "finding some common ground" is necessary, and that vegans shouldn't be so militant, because that undermines veganism
Every movement towards progress or justice has those on the losing side claiming that moderation is the answer. Consider these quotes:
“I must confess that over the past few years I have been gravely disappointed with the white moderate. I have almost reached the regrettable conclusion that the Negro's great stumbling block in his stride toward freedom is not the White Citizen's Councilor or the Ku Klux Klanner, but the white moderate, who is more devoted to "order" than to justice; who prefers a negative peace which is the absence of tension to a positive peace which is the presence of justice; who constantly says: "I agree with you in the goal you seek, but I cannot agree with your methods of direct action"; who paternalistically believes he can set the timetable for another man's freedom; who lives by a mythical concept of time and who constantly advises the Negro to wait for a "more convenient season." Shallow understanding from people of good will is more frustrating than absolute misunderstanding from people of ill will. Lukewarm acceptance is much more bewildering than outright rejection.” -Martin Luther King Jr., Letter from the Birmingham Jail
"But I fancy I hear some one of my audience say, it is just in this circumstance that you and your brother abolitionists fail to make a favorable impression on the public mind. Would you argue more, and denounce less, would you persuade more, and rebuke less, your cause would be much more likely to succeed. But, I submit, where all is plain there is nothing to be argued. What point in the anti-slavery creed would you have me argue? On what branch of the subject do the people of this country need light?" -Frederick Douglass, What to the Slave Is the Fourth of July?
Carnists are imagining themselves to be world-class experts on spreading a position they themselves don't subscribe to. You haven't been convinced of the position, so why should I listen to you on what's most convincing?
100% of the time I have encountered this argument, it concretely means one of the following two things:
Actually, the first point is being highly generous. In a lot of cases, people say they're against factory farming, for instance, but eat McDonald's and buy frozen chicken wings by the gross - So it means literally nothing in that case. At best, it means "I eat meat but am against horse racing - and all that veganism should be against is horse racing. Don't be against meat eating or anything!".
This is the classic line of "It hurts your cause to go after issue [thing that affects me] or to tell me I should [do something more than jack squat]; you would gain more support if you went after something I didn't participate in... or were gentler by recommending I made no changes. I just really want this whole project of ending animal cruelty to be a success, and I'm concerned you're not going to be successful if you tell people to do anything different. That would be like... so sad. You don't want more animals hurt, do you??"
Miss me with that.