Pros
being around great creatives, exposure to the advertisement world/agencies/clients, being welcomed kindly by the staff, most people are nice to interns and do go out of the way to make them feel a part of the office community, benefits to food/beverage, sometimes being able to shadow creatives
Cons
needing to pick/clean up after others constantly, some people are difficult to deal with, passive aggressiveness, not always being seen as a person as an intern, barely any opportunity to move up in the company/be hired outside of being an intern, big drinking culture, some days are very quiet, while some are incredibly busy (understandable)