From the web site All True Bible Stories For Children:

"Mother," Beth interrupted again. "If they are supposed to be spying, why are they visiting a prostitute? I thought that a prostitute was a woman who would let any man put his penis in her so long as he left her a bunch of money on the table by her bed?"
"That is true, Dear One," answered Beth's mother, "but sometimes spies must do strange things to get the job done. Now please, let me tell the story."