Why do you suppose that so many technology start-ups have been criticized for having having a "bro culture"? Why is this problematic from an ethical perspective? Imagine you have been recently hired

Why do you suppose that so many technology start-ups have been criticized for having having a "bro culture"?  Why is this problematic from an ethical perspective? Imagine you have been recently hired at an HR manager at a tech start-up, what steps might take to prevent a Bro culture from emerging in your company? (Recommended length 250-300 words)

and 

Is there anything unethical about food scientist manipulating food ingredients to make food taste good even it requires more salt and sugar than is usually recommended? Is there anything unethical about advertising these to kids? (Recommended length 250-300 words)