Counting FIS World Cup victories is like calling Pete Rose the greatest hitter of all time just because he had more hits than anyone else -- while ignoring the fact that his .303 lifetime batting average is something like #175 all time in Major League Baseball.
It s quite an accomplishment to be the all-time hit leader, but I agree with your comment about average. Also, I would expect a lead-off hitter to be the all-time leader in number of hits, since they would have the most number of opportunities.