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.
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."