Paying for clicks and traffic on social media or in the search engines can be a great option to market your blog. A lot of the information about blog marketing covers the organic options. While some of these can turn your blog into a popular destination quickly the more likely scenario is that it will take time for you to build communities to promote your blog content.
Creating a job board on your site is a great way to make your blog "sticky" - meaning you get visitors returning again and again. It's also a great way to earn some extra cash while also providing a valuable service. Darren Rowse from ProBlogger runs a hugely popular job board where he charges $70 for a 30-day listing. With around 70 listings per month, he's bringing in some solid earnings with relatively little investment of time or money.
The answer is yes. However, I would caution against it. The reason is, when you use a free service, you don’t have as much control over your blog—the free service does. This can be risky, especially if you will rely on your blog for income. A self-hosted WordPress blog is my recommendation and can be started very inexpensively. See my step-by-step tutorial here.