You cannot milk pigs. (Can understand this, even if pigs do produce milk, pig's milk isn't really used by humans)
Slaughtering piglets does not net you a suckling maw. (Just... why?)
Their meat is the same as a boar, which means that the glacial speed of tamed animal q in hafen means it will be months, maybe a year, before it's worth it to use a pig instead of going out and hunting a minimum q boar.
Right now, all that I see ahead of me with my pigs is managing to barely match wild animal q when the world gets reset