Chum Nuggets are small oval-shaped chunks of chum sold in the Chum Bucket. They resemble chicken nuggets from McDonalds, but they are made of chum, and not chicken, and are a parody of chicken nuggets. People eat them out of love for something (the decor, or the slogan) but not necessarily for it's strange taste. A machine tube dispenses chum into a small polystyrene foam container commonly used for takeout at restaurants.
People hated the taste, but due to the decor of the Chum Caverns, they couldn't resist spending money, and eating the chum nuggets.
Plankton's sign, "Chum is Fum" attracted a lot of customers. As in Chum Caverns, people couldn't resist the name of the slogan, and continued to eat chum nuggets despite it's repulsive taste.
Plankton offers some chum nuggets to impatient costumers waiting in line for the Krusty Krab drive thru, but after an old fish runs over him twice, Plankton then says, "Chum nuggets. Get them before... my arm falls off."