I saw that yesterday too. Yesterday morning, I was looking at flights to Vegas and they had a one way flight for $180 for one person. As soon as I changed it to 4 persons, it went up to "regular price". And then last night...it was way up again. I'd like to say that something is glitchy but I think that's how it is....I'm now checking any time I can in case I can find a "glitchy" price.