The plot is a satire of the Ice Bucket Challenge. The fictional Groat's Disease was used in place of a real disease because creator/writer Alex DeCourville did not want to trivialize a real disease. (Groat's Disease originated on Curb Your Enthusiasm. Alex DeCourville wrote it in, with plans to replace it with another fictional illness, but could never think of anything else.)
In explaining the cast change of Bernie, the haircut joke was Rance Martin's idea.
The pizza scene is a satire on McDonald's "Pay with Love Campaign."