Holly Thomas is a British writer and editor based in London. She tweets @HolstaT. The opinions expressed in this commentary are solely those of the author. View more opinion articles on CNN.

London (CNN) Ever since Greggs announced its new vegan sausage roll on January 2, the Internet has been ablaze with opposing opinions. Many have been delighted, with many outlets of the UK fast-food chain selling out of the new arrival by lunchtime. Others however, haven't been so thrilled.

On Greggs' announcement, the TV presenter and newspaper columnist Piers Morgan tweeted: "Nobody was waiting for a vegan bloody sausage, you PC-ravaged clowns." He, and many others, have since continued to lament "messing with the perfect sausage roll." One shopper tweeted a video entitled "how to eat a vegan sausage roll." It shows him buying the roll, then walking to a bin, and throwing it away.

Nobody was waiting for a vegan bloody sausage, you PC-ravaged clowns. https://t.co/QEiqG9qx2G — Piers Morgan (@piersmorgan) January 2, 2019

Now, any discussion of veganism online tends to be an absolute minefield. But for all the associated aggro, plant-based eating seems to be on the rise. One 2016 survey found that more than 540,000 people described themselves as vegan -- a nearly fourfold increase in 10 years. More than 2,000 books are available at Waterstones with the word "vegan" in the title, Google searches have multiplied in the space of a few years, and in 2017, Just Eat saw a 987% increase in demand for vegetarian takeaways.

Reducing consumption of animal products is demonstrably good for the environment and our health, and the new Greggs roll was developed in response to a petition signed by 20,000 people. The idea that there is no interest in or market for a vegan sausage roll is evidently ridiculous. So why claim so?

Holly Thomas

Virtue-signalling is a now-stale phrase born in 2015, which describes people who publicly highlight their support for good causes, but care more about you noticing how worthy they are than the cause itself. Recently, an opposing phenomenon has also gained traction.

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