I believe the 'longer' version of a formula is more useful, and you would be able to know what chemical it is by looking at it. On the other hand, empirical formulas are the shorter form, and so i am not quiet sure why you would want that.
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When a compound is analyzed, you get the empirical formula, since C6H12O6 has the same composition (% of each element) as C5H10O5, C4H8O4, C3H6O3, C2H4O2 or CH2O. So it is not that we particularly "want" the empirical formula rather it is that we end up with the empirical formula.