With the RSA Certificate you greatly increase your work opportunities. You never know when your job may come to an end or when you may need some extra cash. The RSA Certificate will allow you to work behind a bar or as security staff in venues that serve alcohol. Just about any job that requires you to be around the service of alcohol requires an RSA Certificate.
So think about your local pub or bar. Who works there? The bartenders will definitely require one, the waitresses, the door staff, bouncers, security. Are there any other positions in your local venue eg concierge, gaming attendants? There are lots of jobs that require a certificate. What about if you are going to work for a catering company? You may go to various places and be required to serve alcohol. These jobs will also require an RSA Certificate.