Visible crew/equipment: When R. William Neill is watching the news on the TV, in the TV station, you can see a camera reflected in the right hand side of the TV screen. (00:03:20)
Visible crew/equipment: When Karen enters the phonebox with the yellow smiley sticker inside, you can clearly see the cameraman in the glass of the phonebox, as he pans round. (00:03:25)
Visible crew/equipment: When Karen enters the pornography store, to meet Eddie, as the camera lowers to follow her, you can see it reflected in the glass of the front desk. (00:07:45)
Answer: I think they were purposely brought there to both join the colony. Marsha, who desired Bill, was impatient and bit him. As for not being mad at her, the Colony was slowly turning to her leadership, instead of the Doctor's compassion treatment.
Why would the colony want Bill and Karen to join them?