Finding gender affinity for businesses
Since you're only interested in the gender affinity of businesses in your dataset, no model is needed.  You can compute gender affinity directly:  For each business, find the total number of customers, the total number of male customers, and the total number of female customers.  Then $Pr(Male) = \frac{males}{total}$ and $Pr(Female) = \frac{females}{total}$