Allow me to elaborate. In politics we hear about "pork barrel spending" and how congresspeople try to "bring home pork" to their constituents. I just got to thinking: is this because pork used to be more expensive? It seems pretty ubiquitous these days.
It appears to have had more to do with the feeding of slaves than price.
I have some photocopied pages of "A Little History of Pork", by Chester Maxey, from the 1919 edition of the National Municipal Review. (I've just checked and it is available in Google Books.)
Essentially, the article says the feeding frenzy of slaves to get at newly issued barrels of pork was similar to the way politicians react to any opportunity to spend money on their constituents and ensure reelection. (That bit is on page 693)
It's rather the opposite. Historically, pork, especially salt pork, was the cheapest meat that was widely available. The image of people (esp slaves) crowding around a newly-arrived barrel of salt pork is where the image behind the phrase "pork-barrel politics" comes from.