Yes. They say on their site how long it takes, so you must have missed it when you ordered.
Zulily is a flash sale site and does not have their own warehouse, just like Gilt and Hautelook. They fill orders on demand, so you order, the company who warehouses the product sends it to Zulily, and Zulily then sends it to you.
Hautelook saw shipping times decrease when Nordstrom bought them, but they're still slower than your average site. That's their business model.