All Goodwills price items differently. It is up to the descretion of the employee in the back room that is pricing things that day. They just give you a lot of giant rolls of price stickers at different increments and tell you to make your best judgement on what you think the item is worth. That's all there is to it. Blame the employee that put that price on it, not the corporation as a whole.
People at my Goodwill put $60 price tags on 10-15 year old Keurigs that are clogged to hell, when you can get a new one for $40-$50 now.
Your best bet is to go on half off days, but I can guarantee that that Kirby would be gone in the blink of an eye. My Goodwill prices vacuums from $19.99 to $29.99, but if you go on half off day it takes some of the edge off the price.
One time I went in there they had a Mighty Mite, complete with floor nozzle and bags and everything, for $4.99. I originally thought it said $14.99 so I didn't consider it, especially since it smelled likethe locker room of a football stadium but it wasn't until I looked at the photo later that I seen it said $4.99. It was a half off day too. I went back the next day, it was long gone.