While in a foreign country, you are subject to local laws, even if you are a U.S. Citizen. It is very important to know what's legal and what's not. Simply drinking in public may be considered a criminal activity by local authorities, and this can carry unknown penalties.
If you break local laws while abroad, your U.S. passport will not help you to avoid arrest or prosecution, and the U.S. Embassy cannot get you out of jail.
Additionally, according to the SDSU Code of Student Conduct, you are expected to conform to campus policy, even when you are away from campus, and even if you are in a different country. Review Standards for Student Conduct.
“Students are expected to adhere to the Student Conduct Code. They are expected to be good citizens and to engage in responsible behaviors that reflect well upon their university, to be civil to one another and to others in the campus and surrounding communities, and to contribute positively to student and university life. This includes upholding all published university policies, rules, regulations, or presidential orders.”