The good thing about Facebook likes, is that with website cookies, when you like a page, or visit a website, a lot of advertisements will be related to those pages. For example, if you visit the page of Cafe Montagna, other resaurants and food ads could pop up on your home page. Because there are so many cafes, restaurants, and general food products being advertised, this is actually a really effective way for any business involved in food to advertise.
For example, the other day, I went on a website talking about food in Australia, and then I started seeing ads for the Country of Origin Labelling for Food. Basically, they're spreading the fact that new stickers will be put on foods so that we'll be able to tell where it comes from more easily.
Given everyone's recent obsession with organic and healthy food, it's pretty logical to assume that people care about where their food is from, and if it's an Australian product or not. So, making sure people know new labels are coming, and what they mean is a pretty smart idea, and advertising it on Facebook ensures people will be in the know.