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footings a beam or a slab?

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I have a case where I have a footing that is 24 inches wide and 16 inches
deep.  I found that the footing only requred minimum steel reinforcement.  In
the longitudinal direction I used 3 #5 bars and in the transverse direction I
used #4 @ 6".  I was told that my #4 bars were not needed and that I can just
space them at 18 inches.  This was argued that the footing acts like a beam,
which I understood, and in a beam you don't need to satisfy the 0.0018bt
critiria.  But as I was reading the ACi.  In the flexural reinforcement
section 10.5.4 it states that "For Structural slabs and footings of uniform
thickness the minimum area of tensile reinforcement in the direction of the
span shall be the same as that requred by 7.12.  Maximum spacing of this
reinforcment shall not exceed the lesser of three times the thickness and 18".
If my footing acts like a beam, does it span the length of the footing or does
it only span the 24 inches in the transverse direction.

What does everyone else use as the minimum reinforcement for the transverse
direction for a 24 inche wide beam.

Thanks in Advance

Marlou B. Rodriguez, EIT
Robert Englekirk Inc.
Honolulu, HI