Depends what it is. Sometimes I check for artificial sweeteners because I try to avoid most of those. I also check for sugars in drinks because some drinks have terrifying amounts of sugar in them. I hardly ever drink fizzy drinks these days so when I do I find the amount of sugar to be verging on unpleasant.
Sometimes I read the labels just because it's like the nutritional equivalent of a train wreck in slow motion. That's often more about the entertainment value of finding that a "serving" is 22% of the small pie I can fit in one hand, because some genius decided that the obvious thing to do is cut a pie into 4.5 servings. The reality is more likely that someone would cut the pie in half or maybe eat it in one sitting, and the entire pie contains 478% of your recommended daily sugar intake.
When the item is something you'd cut into slices like bread rather than like a pie, and the serving size is so small you'd think they were slicing meat to put in a sandwich to charge $85 at a ballgame, a slice so thin you'd be able to see through it, I wonder what planet these people are on. But then I figure they are just massaging the "serving size" so they can quote numbers that the average person will think are OK, because the average person probably doesn't stop to consider what they call a serving and what the label calls a serving.