Are you automatically critical of folks who drive "gas guzzling SUV's?"?

A couple of times this week I have seen that phrase, gas guzzling SUV’s said with derision. So I am wondering, do most feel as if owners of these guzzlers are ruining the environment?

What if they are very environmentally minded in all other areas of their life, but they happen to just like or need a big car? Does that make them the enemy? Are they somehow worse than someone who drives a small car but has a large family, uses lots of plastic bags and leaves a huge footprint in other areas of their lives?