Scope magnification in and of itself doesnt't affect price if the rest of the scope specs stay the same. To increase magnification on a fixed power scope you just install an eyepiece of shorter focal lengh. They could market one magnifying a 100x or more for the same price but it would worthless unless you want to shoot at the moon. There is a lot more more to any optical device than just magnification. The quality of the glass, coatings,mechanicals, internal baffeling to increase contrast to name a few. I recently put an SS scope on my Bushmaster and went with the 10x model. I would have bought an 8x one if it were available. Thats plenty of magnification for me and makes for a better all round scope.