Answer:
In the article "Building for Pests", the author compares how people treat "pets" and "pests" because she wants to show that people have different ideas of "pets" and "pests." For example, in some parts of the world, some animals are considered valuable, so they are called pets, while in the other parts of the world those animals are considered "pests". She gives an example of pigeons, which are considered as pests in North America, while in Belgium and Turkey, these animals are raised for pigeon racing.
The main objective of her article is to change people's perception of "pets" and "pests" and their treatment, in order to improve their living conditions.