I came across this new product from the Breyers brand of frozen yogurt, and noticed the odd spelling, "Yogourt". Then I noticed that this product is marketed in Canada.
I was aware that yogurt is often spelled "yoghurt", with the additional "h". But I wasn't aware that that folks in Canada, and I presume in Britain and other commonwealths, spell it with the additional "o".
I guess it's just like how they spell other words incorrectly, like "colour" and "analyse".