Any company that orchestrates a job fair will tell you that Job Fairs are a very effective resource to finding a job.
I, on the other hand, will tell you they're a waste of time.
Job Fairs are built for companies, not job seekers. Job Fairs are based on an advertising business model, which is precisely how the organizers make their money. The model is not about getting people jobs; it is about creating enough hype and promoting traffic in order to entice potential clients to purchase space. Simply put: Job Fair companies sell advertising. That advertising comes in the form of booth rentals, company sponsorships and print advertising. The larger the space, the larger the revenue. The larger the ad in the Job Fair directory the larger the cost. Due to contrary belief, the goal of a Job Fair company is not to get people jobs, but instead to drive enough traffic to sell ad space.
The advantage for companies is that it is an inexpensive way to promote and build brand awareness around your firm especially if you are always hiring due to attrition. So for those companies that have a lower need for talent, this type of model gets them in front of many people. These companies typically have a high turnover rate and need to constantly keep the funnel full of applicants. For them the business model is bodies in seats. After 30 days, if they retain 2 people out of 50, they consider themselves successful. The point being, the next time you are at a job fair, look around the room and see what kind of companies are there. You will typically find well branded companies with jobs that are not very appealing. Because of the low cost of entry for these firms, there is limited risk and little importance placed on the actual candidates that visit the booths. It is more about driving a consistent message to the public and yelling from the roof tops that a company is hiring. Companies do not attend to find a specific skill set, instead they are there to speak with the masses.
In conclusion, Job Fairs are about volume. As a result, I cannot say there is any advantage for job seekers. I would love to tell you that Job Fairs are a great resource to getting a new job, but it is simply not true. Most of the opportunities are high turnover or entry level where past experience is not necessary. If you are just starting out in your career and have no idea what you want to do and have time to experiment, then by all means give it a shot and at least gain some experience of what Job Fairs are like. Otherwise, if you are successful in your career, use your network, search firms, Linkedin, Facebook and other social media to spread the word and target real people at real companies with a real need. The time you spend at a Job Fair could be spent digging up qualified leads to truly help you advance your career. The goal is to find a career, not just a job.
Now that you know the model behind Job Fairs you can decide for yourself if they are worth while. If you get lured into a Job Fair make sure you are not wasting time and if you find that you are, just leave.