The spatula in the background of Scuba Gragas artwork most likely belongs to Urf.
Hillbilly Gragas is a reference to the "hillbilly" stereotype.
Santa Gragas skin is a reference to Santa Claus, a figure in Western culture who represents the mythological and folkloric aspects of Christmas.
The term Esq., as used in Gragas Esq. means "esquire", which is an unofficial title of respect, having no precise significance, which is used to denote a high but indeterminate social status.
The bottle from Gragas' Esq. skin says "Gragasse brute". However, in the in-game skin art, the bottle will actually say "Responsibly", possibly a reference to the recurring theme of "Drink Responsibly" at the end of most alcoholic beverage commercials.
In the splash art for Oktoberfest Gragas you can see Gangplank, Olaf, and Ashe all dressed fitting the Octoberfest Theme. You can also see the glove of Teemo in the bottom left corner holding a drink.
Gragas brews and sells his own brand of alcohol known as "Graggy Ice," and has made a business deal with Singed to mass-produce his product in chemical plants based in Zaun.
He made a deal with Queen Ashe and King Tryndamere to lease the Avarosa Iceflow from Freljord for 9,000 years for the constant water supply to his brewery expansion in Freljord that is constructed entirely of ice.