Why do people that cooks crystal meth use sudafedrin is it because its one of the ingredients?

Well, honey, you hit the nail on the head! Sudafedrin contains pseudoephedrine, which is a key ingredient in making crystal meth. Those folks cooking up a storm in their makeshift labs are just trying to get their hands on that sweet, sweet pseudoephedrine to whip up their illegal concoction. Just remember, cooking meth is not only illegal but also extremely dangerous, so stay far, far away from that mess.