"Negrobilia" is found offensive by many. There's a collection of it at Chicago's Stony Island Arts Bank
http://www.chicagotribune.com/entertainment/beingthere/ct-arts-bank-stony-island-ent-0705-20170628-column.html that, when you see an image like this Mammy in context (alongside "Whites Only" signs), made my stomach churn.
From the article:
'a postcard showing two black children, the caption reading, "I'm sending you a pair of black kids." Asked what it meant, he said it was likely an advertisement for a pair of gloves. He smiled at the absurdity.
...
"The more I collected of this, the more I realized the range of stuff that had derogatory black images was endless," he said. The intended message of the advertising was often innocuous, completely disconnected from the racism of the images used to sell an item.
Indeed, to poke through Williams' collection is to be reminded, harshly, of how commodified and ordinary racism has been, and arguably is, in American pop culture. "It was big companies and small companies doing it," he said. "I don't want people to forget when there is no downside to denigrating a race of people, companies will do it."'