Judging from postcards and cartoons, the early 20th century was not a fun time to be a waitress. However hard working, competent, or skilled in dealing with demanding situations they may have been [see recent op-ed on how much skill serving takes], there was no recognition of that in popular images.
Quite the contrary. The images were of two basic types. Either female servers were shown as incompetent or as objects of fantasy who were open to the sexual advances of their customers.
All but two of these images in this post are from 1906 to about 1915. The gum chewer is from the 1920s.
The reasons for these degrading images could be many. Joke-style postcards were designed to get men to send postcards, an activity that they were less inclined to do than were women. Almost all joke postcards derived humor from insulting others, whether women, Blacks, immigrants, or the poor. On several of the cards in the post, the women illustrated are Irish immigrants, a status that was generally portrayed as both stupid and ugly. Women who were in the public eye, such as actresses, department store clerks, or restaurant workers, were evidently considered fair game, possibly out of resentment that they strayed outside the realm of church and home or because they appeared in public without male protection.
Later postcards mostly dropped the theme of incompetence but images of sexy bimbo waitresses persisted for decades, as for example on this postcard mailed in 1946.
© Jan Whitaker, 2015
It's great to hear from readers and I take time to answer queries. I can't always find what you are looking for, but I do appreciate getting thank yous no matter what the outcome.
Restaurant-ing through history 
Jump 70 years and we have a massively successful US restaurant chain devoted entirely to this pastime – Hooters – which is acceptable and successful enough to be in malls all over the country just like any other chain. Nothing has changed really.
Largely true, except for one thing which is that now women can be servers in luxury restaurants. You would never find that in the 1950s.
Reblogged this on Chef Ceaser.
Hmmm, except maybe I mixed up two restaurants. One was the quiet woman: http://www.quietwoman.com/qwoman.php and the other was the perfect wife (in VT).
The quiet woman had no head and the perfect wife brought popovers?
Speaking of insulting–there was a restaurant in CT? I think? Called “the perfect woman” and it featured a shapely female body with no head. (and it was odd in other ways; the waitresses walked around with tins of popovers slung around their necks.)