The same question could be asked of people who live in larger-than-needed houses in cold climates, drive larger-than-needed cars, take multiple flights a year for vacation, have not installed roof solar systems yet or (and this is particularly taboo) have large families, e.g. 5+ children, far beyond the replacement rate.

I'd like to pose a serious question to you as well: how do you justify singling out meat eaters over any one of the categories I list above?

You'd have much better luck asking people to cut their consumption of meat by 50% instead of trying to guilt trip them into becoming complete vegetarians.

I'm not making a judgment call here. The listed groups are not in any way worse than one another, but they all have something in common - potential to reduce their impact on the environment. I think it's quite silly to single out meat-eaters as the ones who have to justify their behavior, aside from the fact that the article at hand mentions the meat industry.