Lobsters were so abundant in the early days—residents in the Massachusetts Bay Colony found they washed up on the beach in two-foot-high piles—that people thought of them as trash food. It was fit only for the poor and served to servants or prisoners. In 1622, the governor of Plymouth Plantation, William Bradford, was embarrassed to admit to newly arrived colonists that the only food they “could presente their friends with was a lobster … without bread or anyhting else but a cupp of fair water” (original spelling preserved). Later, rumor has it, some in Massachusetts revolted and the colony was forced to sign contracts promising that indentured servants wouldn’t be fed lobster more than three times a week.

“Lobster shells about a house are looked upon as signs of poverty and degradation,” wrote John J. Rowan in 1876. Lobster was an unfamiliar, vaguely disgusting bottom feeding ocean dweller that sort of did (and does) resemble an insect, its distant relative. The very word comes from the Old English loppe, which means spider. People did eat lobster, certainly, but not happily and not, usually, openly. Through the 1940s, for instance, American customers could buy lobster meat in cans (like spam or tuna), and it was a fairly low-priced can at that. In the 19th century, when consumers could buy Boston baked beans for 53 cents a pound, canned lobster sold for just 11 cents a pound. People fed lobster to their cats.

https://psmag.com/economics/how-lobster-got-fancy-59440/

The urban myth overwhelmingly seems to be that prisoners were primarily fed lobster, and a recurring unsubstantiated story of servants refusing to eat it several times a week. Not in contestation is that it was a lower-class food, that it was cheap, or that prisoners in the period certainly were fed lobster oftentimes precisely because it was cheap.