Almost all of Apple's stores in the United States have stopped offering the HomePod for in-store purchase and pickup, with the speaker listed as unavailable in nearly all retail locations.
In the Bay Area, for example, there are no HomePods available for purchase, and the same goes for New York City, Los Angeles, and other major cities. There are a couple of stores, such as the San Diego store at UTC that still have stock available, but for the most part, Apple appears to be ceasing HomePod sales in its retail locations.
Note that this applies to the white version of the HomePod only, because the Space Gray HomePod has been sold out for months now.
It is not clear when Apple made this change, but the HomePod is still widely available for next-day delivery in many areas, and it is still available in stores in other countries outside of the United States, such as Australia.
Apple officially discontinued the HomePod in March in order to focus its efforts on the development of the HomePod mini. At the time, Apple said that the HomePod would continue to be available through the Apple Online Store, Apple Retail Stores, and Apple Authorized Resellers "while supplies last."
With the HomePod disappearing from retail stores in the United States, it's possible that supplies of the white version are now dwindling, but Apple may have also simply decided to limit the sales of a discontinued product to the online store.
There are rumors that Apple is working on new HomePod products to accompany the HomePod mini, including a HomePod with a display and a camera and a version that combines an Apple TV with a HomePod.
