As a rule Small and Medium businesses should advertise to drive sales directly. Include a clear 'call-to-action', along with some sort of offer; a time sensitive promotion is a good way to do this.
In your PAID advertising, spend your money wisely small business owners. You should be focusing on generating transactions, and identifying whether or not you are generating a positive return for your marketing dollars. You can (and probably should) focus your brand building strategies in free channels like social media.