People have enjoyed asparagus for centuries, and there are etiquette rules for eating it. In the 1950s, the etiquette involved cutting asparagus in half before eating it.
Emily Post's 1975 "The New Emily Post's Etiquette" suggests that the "ungraceful appearance" of eating asparagus with liquid or sauce dripping from it was at issue.
Cutting a spear in half before eating it with the fingers was considered the proper way to consume the vegetable in public, avoid a social faux pas, and reduce any potential mess.
Most modern etiquette guides, including famous British etiquette bible Debretts, suggest that asparagus not served in a sauce may be eaten with the fingers.
The tougher end of the asparagus should not be eaten. In the 1950s, this would not have been an issue since the asparagus would not be served with the hard end still present.