You can mist Pings, it depends on the type of plants, their growing conditions and the time of year.
I wouldn't recommend misting temperate or SE USA Pings, although these plants do enjoy growing in fairly high humidity.
Some growers (not many) water their Mexican Pings using an overhead misting system all year round, I don't, I water on a shallow tray system allowing the plants to dry out a little between waterings. Many of these species are very hairy in winter (eg. P. gypsicola), when they are in their succulent growth form. It is thought that these hairs have evolved to trap mist in the air to help them avoid desiccation during the cool, dry winters that these plants experience in nature. I give my plants an occasional (no more than once every week), light misting in winter, to try and replicate this and have yet to lose a plant over winter, the plants receive no other water through the winter.
It is important to have good air circulation for Pings, especially if you mist them, in order to avoid fungal problems. I wouldn't recommend misting them in an enclosed space, such as a terrarium, unless it had a fan installed.
Pings generally feed on very small insect prey, such as gnats, the ones you see stuck to their leaves are caught prey. Pings have sticky glands on their leaf surfaces which trap small insects, and other glands which release digestive fluid containing enzymes, which digest the prey, this is then absorbed through the leaf and the plant has fed (quite similar to sundews, without the moving tentacles). Get a good magnifying glass and take a close-up look at the leaves of some Pings and you'll see the glands. Some Pings are very glandular and almost look like sundews, I grow a P. gypsicola x P. moranensis hybrid (Frazer's Red Leaf) which in Summer, is almost as sticky looking as my D. schizandra.
Cheers
Vic