When a werewolf customer shops at a small business they will invite themselves into the owner's home either when they decide to leave the business, or when the business closes. They cannot be sent away through social interactions. Using the "Send everyone home" action when another visitor is present only sends the non-werewolf visitors home. They sleep in any available beds, cook, bathe, etc. The only way to get them to leave is to have your Sims leave the lot and come back later.
I have only seen this happen with werewolves, and it has happened with every werewolf customer who's attended a small business since the most recent update.
