The Website was designed in-house with you in mind, not some corporate bigwig.
Fiona makes contact with an oil company bigwig and uses the knowledge of her extra-marital affair to blackmail her for information.
If you're meeting with a bigwig client, the president of your company (or any company) or anyone whose company might make you even consider dressing up a bit more than usual, then you're right - you should dress up.
You don't have to be a celebrity, royalty, or a political bigwig to visit San Francisco, the City hosts events and welcomes tourists of all persuasions, nationalities, and various levels of ignobility.