Very interesting to see the 'brogans' enter this conversation about (childhood) insults. In my recollection, 'brogans' were not only sturdy work boots but specifically IRISH work boots, and saying someone wore them was lumped in with the idea of 'country' or unsophisticated ('just off the boat' and 'just fell off the turnip truck' are used very similarly) and with the assumption fostered in England at one time that the Irish were somehow less than human, which carried over into the 'no Irish need apply' mentality in the U.S. The word 'brogan' was Irish Gaelic, as was 'brog' for a work shoe, which became 'brogue' in English (presumably so it would not be pronounced 'brogg' to rhyme with hog). I have read that the Irish 'brogue' or lilting accent now widely admired in the U.S. apparently got the term from an earlier time when being Irish was not a good thing, and the accent was described as if it were clumsy, clumping along, 'country' and unsophisticated.