Zhang Zian had seen a basket hammock chair at someone else's home before. He felt that the chair seemed quite cozy when he saw a couple sitting in there and flirting, or when he saw a child reading a book or playing on an iPad in there. Since he had neither a girlfriend nor a child, he forgot about the basket hammock chair very quickly.
Since there was no suitable bed for π, Zhang Zian remembered that the basket hammock chair might be a good choice for π, so he came up with the idea to shop for a one online. This thing would be expensive in a brick-and-mortar store, while shopping for it online would be more convenient and there would be more styles to choose from.
The biggest advantage of shopping in a brick-and-mortar store was that π could try out a chair to see if it fits. Let alone that π couldn't leave the pet shop, but even if it could, going outside would cause troubles.