© PA Images / Amy Sancetta / AP
Laura Howells dropped the packet whilst eating a takeaway meal in her car outside B&Q in Trostre, Llanelli.
The Sun reports that a council official spotted Howells and issued her with an on-the-spot fine of £75 ($118.16) for littering.
After the 24-year-old failed to pay, she was taken to Carmarthen Magistrates court and ordered to pay over £400 for the offence.
Howells said: "I felt sick when I found out how much it cost me - it was only a salt sachet.
"I was eating lunch in the car and must have dropped it by accident. I am not the type of person who ever litters."
Jim Jones of Carmarthenshire Council said: "Cleaning our streets costs £2.2million a year. Dropping litter is against the law."
