IMO it doesn't matter whether VP8 costs one cent or one dollar; if you've already paid for H.264 then even one cent for VP8 is a waste of money. And those who aren't willing to pay (Mozilla and Opera) are not even willing to pay one cent.
Historically every new codec has been cheaper (despite containing more technology), so I expect VP8 to be cheaper than H.264, but H.265 may be cheaper still.
Historically every new codec has been cheaper (despite containing more technology), so I expect VP8 to be cheaper than H.264, but H.265 may be cheaper still.