Is promoting goods on internet cheaper  

Consider what you faced a decade ago, when there were only selected ways to promote your goods offline. The television was the best among the whole lot, and the money that you had to spend to air your ad in television was too expensive, but with the advent of internet, things changed dramatically for the firms.
Internet made the ads cheaper, and in fact, if placed on the right site, you can get millions of views in a very short time, by spending just few dollars, compared to millions that you had to shell out on other multimedia channels.