Green’s Dictionary of Slang

cookie-pusher n.

also cookie-duster
[SE cookie + pusher; the cakes that such men are continually passing around such tea parties or that waitresses serve in cafés]
(US)

1. [1920s+] an ambitious, but lazy, man, esp. a government career man, a sycophant.

2. [1920s+] a young man who errs on the ‘feminine side of life’ – tea parties, conversation, the niceties of dress and of gossip, art rather than sport etc; thus cookie-pushing n.

3. [1930s–50s] a waitress.