Frank J. Wilstach, comp. A Dictionary of Similes. 1916.

Snug

As snug as a pig in pea-straw.
—Richard Davenport

Snug as a parson.
—Gustave Flaubert

Snug
As a bug
In a rug.
—Benjamin Franklin

I’m as snugly shut
As a glad little worm in the heart of a nut.
—James Whitcomb Riley

As snug as a snag in a bog.
—Eugene Fitch Ware

Fitted as snugly as bits in a puzzle.
—Edith Wharton

Snug as a child that hides itself in sport
’Mid a green hay-cock in a sunny field.
—William Wordsworth