Finger painting was always popular when I was a elementary school art teacher. Who doesn't like squishing wet gooey stuff between their fingers? When I taught a painting class to the older children they loved to play with their paint trays after they were done, making a wonderful mess out of the remaining paint. And don't get me started on paper mache, always a hit with any age. You could really lose yourself in that gushy paste!
Pigs might love paint or paste too if they had the chance, but they instinctively know that mud is the superior ecstacy.