My informant is my mother, who has heard my father spout says and folk speech all their married life. I’ve grown up hearing them myself. My father is prone to using such phrases in everyday conversations. Here is an example.
“Well your father says suck eggs all the time. I don’t know what it means or where he got it from. It means buzz off in a not so nice way. Or “suck eggs on them” like they don’t matter or screw them. If you are complaining about something someone did, he’ll say “well suck eggs on them”.
This is an example of a folk speech, a folk saying with a connotative meaning. It comes from the idea that one looks very silly sucking on an egg and therefore saying one should “suck eggs” is a kind of a curse, like screw them. It means that the person who is complaining is the “good” party while the person being told to suck eggs is the “bad”. It was originally an English saying, meaning something similar. It is used as a derogatory term, a curse, but usually not in the presence of the person the curse is directed towards. It is usually between a person telling another of something another did and that second person agreeing with the first on the irritating qualities or action of that person.