Every sport with rules subject to interpretation — fouls in basketball, holding in football, double contacts or catches in volleyball for example — are inherently asking for trouble. In and out in volleyball, out of bounds in football, safe or out in baseball, for example, are much easier to ref. Throws are difficult because where do you draw the line?
I know where I’d draw the line — ban them all.
Just be thankful our rules aren’t as impossible to ref as football’s. And that they aren’t all subjective like gymnastics and ice skating.