What became of the cheaper cuts of meat that were once on sale?

Like oxtails,they probably became the 'in' foods for expensive restaurants,and now too expensive for the general public.

We buy 'end pieces' of bacon at Walmart. It's cheaper.

shoulder ham is also often called Boston Butt. yeah, I know its not from the butt but thats what its called now here in the US.

As to collar bacon, I would ask your butcher or the meat guy in your store. they may have more information.

If they aren't bought within a certain time, they might be sold to make dog food, or thrown away.

ger