Actually, what always get me mad is people that use "is like comparing apples to oranges."And if that makes you mad, you probably need therapy.
The basic problem of the expression is that if you can't compare apples and oranges, while both are fruit. Then you can't compare green apples and red apples, while both are apples. Because the rule is that they can not be different types (type fruit or type apple). You are however allowed to compare a green apple to a green apple. Or in the case of FFXI, you can compare WAR to WAR, or SCH to SCH. Don't even think of mixing jobs.
So in the future, it is much easier to just say "Shut up" than to tell people they aren't allowed to compare things because you say so.