It’s not universally true, even in the US. Tesla, for example, wants to sell cars directly from their stores. That’s not possible in all states, however. So in those states, Tesla’s stores are just “showrooms” and a customer buys a car from a website.
One ironic example is Texas. Even though Tesla is now based in Texas, Texas state law prohibits Tesla dealers (which are owned and operated by Tesla) from selling directly to the public.
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