Do you need to walk micro pigs?

No.

Buying the leash and harness was a PURE waste of money. Not only was it difficult to put on the pig, made it get stressed, and was hard to adjust- GUINEA PIGS ARE PREY ANIMALS. They will run at the slightest loud noise, strange environment, and can can get injured if they pull on the harness. I was stupid when i thought "Hey, maybe g-pigs are like dogs and can go on walks too!" WRONG.

It can be the worst mistake of your life giving your g-pig a walk. It can end with poisoning your pig, killing your pig, or losing your pig. It's just not worth the risk.

If you want to give your pig fresh air and grass to nibble on- build a pen, place your pig in it, and watch it so nothing gets to it. Walking a pig to look "cute" is not even a good enough reason.