After the drop deadline, you must contact the officer or director in charge of the event. The events that we put together, especially with the firms, it's not good etiquette to miss it. Most often they remember who did not attend. This could adversely affect the chances of you getting a job there. Generally, cancellations on the same day will result in negative points being given, unless you have some strong and compelling reason in not attending.
Alumni are welcome as well as other chapters around the Bay Area.
This will be a good event to close out the semester.