I think that nothing is written in USA about using English, but in Spain, our Constitution says (art. 3), about Spanish, that all the citizens have the duty of knowing it and the right of using it. The same with the other official languages in our country, whose linguistic rights are considered in their regional Statutes. So, I don't believe your boss is impolite but realistic; knowing the official language of a country opens doors. Another thing would be that people with other language speak this language in their circle and with their family, and it is normal that if you speak Spanish, they prefer to speak Spanish with you than English. But there's nothing wrong if they learn English.
