It's giving them a lot of attention, while also providing their brand slogan.
Gatsby Mansion is a spectacle as referenced in the book multiple times along with the guests.
Explanation:
Gatsby took great pride in the size and stature of his wonderful mansions in which he hosted the biggest who's who of the country and threw great parties which were attended and anticipated,
His mansion was supposed to be gigantic and the source of envy for many of his competitors who wondered where he earned the money from to have such a lavish lending.
The mansion comprised of multiple dining halls, gaming rooms and a grand deep swimming pool in winch Gatsby eventually drowns.
