Presuming that older people are more prejudice doesn't recognize the fact that younger people fill the ranks of most hate groups and are the most active and outspoken members. The only way to combat it is to speak about and be actively against it, which is what she is doing, not sit around and wait for a magically less biased generation to come along - that's not going to happen. Silence only helps the oppressors and blaming the victims only maintains the status quo.
Her menu is posted outside of her cafe (so people know what she is serving before they walked in - which includes traditionally British dishes as well) and the sign was posted after it happened repeatedly (to the point her customers thought she should have done so sooner).
A meet-up there sounds lovely ThingummyBob
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