Green’s Dictionary of Slang

1. smart, fashionable [shoe n. (6)].

1956		H.S. Thompson letter 11 Nov. in Proud Highway (1997) 29: Good Luck and here’s hoping that you’re always ‘shoe’.
1997		(ref. to 1950s) H.S. Thompson Proud Highway [footnote] 29: ‘Shoe’ was a popular period term that meant ‘extremely Ivy League’.

2. (US black) negro, black.

1965

H. Rhodes Chosen Few (1966) 10: Last time I heard, Mistah Chawlie had all you shoe marines gittin’ your black asses shot off runnin’ errands.