Well done on selling all your pigs, and I am sure they have responsible homes.
I am very surprised to learn that you can get a CPH number if you live in a flat or have no land. Who in their right mind would keep animals such as pigs in a flat? Although, I did enquire about a calf for sale, and the seller informed me it slept on her bed.......goodness knows what happened to it. I did not take the matter any further as the seller had no eat tags in the animal nor did she have a holding number, and she wanted £600!!!!
The mind boggles as the owner said she would keep the calf if she did not get £600, so I have this image of a fully grown cow lying on a bed.
"hangbag pigs" will be a phase, and then we will see people tire of them, and they will be up for sale. Pigs should as you rightly said be outside, and the sooner people realise this the better.