OBJECTION TO THE OBJECTION'S OBJECTION! 
Cero is a strong and swift spirit energy-based attack used by upper-level Hollows, Arrancars, and Vizards.
The only beings that we have seen using Cero are Menos, Arrancar, and Vizard. Bala in itself has only been used by Arrancar, to my knowledge.
Using this, it can be inferred that normal hollows are unable to peform these moves becausethey lack the spirit energy control and reserves to form the attack. This is the reason why hollow have their own, unique powers, as to not leave them defenseless. In this case, it would be fire.
*Prepares for comeback*
