I should think Penny's question is more about the information about her stored elsewhere, rather than the I.D. information inside a cookie. I've noticed that 'elsewhere' information, too, and the internet seems to be eternal, so it stays 'somewhere.'
A little creepy. Is my computer telling others that 'I'm online, sell to me,' or is Mudcat being used as a conduit for sales information?

It is enlightening to websearch yourself. It's surprising how much information about you is available, in your various personas.