Abe is spending a third of his budget on food, so he spends $3000 / 3 = $<<3000/3=1000>>1000 on food.
He spends a quarter of his budget on restaurant supplies, so he spends $3000 / 4 = $<<3000/4=750>>750 on supplies.
Thus, he spends $3000 - $1000 - $750 = $<<3000-1000-750=1250>>1250 on employee wages every month.
#### 1250