wheel bolt pattern confusion

[blind34_1]

okay I thought I knew how this works, but obviously i am wrong.

I went to the junkyard the other day, looking for better wheels for my escort (94 escort, standard). I came across some wheels with very new tires from a focus (not sure on the year). I didn't think they would fit, but I tried anyway. Sure enough, they wouldn't go on, the hole spacing on the focus wheel was too far apart for the escort. i also tried some contour wheels that looked alright, same result. big surprise, i go home.

Well then I get online and check bolt patterns. more than one site says that escorts and focuses have 4x108mm. wtf? As I understand, the 108mm is the diameter of an imaginary circle drawn around the studs. if this is true, then why the heck wouldn't the focus wheels line up?

I'm sure it's something very simple that I completely missed. Somebody please clue me in!