On the day, we do give them a bit of grub to get them into the trailer, and apples (I omitted to say I give them their morning feed the day before, it's the evening feed I miss out). Good idea about the bread, I think they deserve that last treat.
On another note, abattoirs are getting more strict every year, and it is becoming prohibitively expensive here for the smallholder to keep a couple of pigs for their own consumption.
Pork is so much cheaper (and a lot less work) from the supermarket, but I find it pale and not as flavoursome as home-reared pork (plus I just like keeping pigs). I make my own sausages, black pudding, pates etc, and I take a leg from each pig to a specialist curing facility to be air-dried for three months. The resulting 'parma' type ham is THE best (fry it off a little and the result is the most fab bacon baguette ever).
Our pigs are happy pigs, reared with the sun on their back, dirt to push their noses into, and tasty treats to eat. For that I will pay the extra.
Best wishes.