Paul McCartney has an important request for Starbucks: Stop charging more for plant-based milks. If you have been to a coffee shop any time over the last few years, you might have noticed they charge 50, 75, sometimes even 100 cents for almond, oat, soy, or other types of plant-based milks. (Starbucks charges 70 cents, at least in the US.) McCartney has partnered with his friends at PETA to implore outgoing Starbucks CEO Kevin Johnson to make this change before he leaves the company next week.

As Billboard reports, McCartney has issued an open letter to Johnson. “It recently came to my attention that Starbucks in the USA has an extra charge for plant based milks as opposed to cow’s milk,” McCartney wrote in his letter. Here it is in full:

Dear Mr. Johnson,

It recently came to my attention that Starbucks in the USA has an extra charge for plant based milks as opposed to cow’s milk. I must say this surprised me as I understand that in other countries like UK and India, there is the same charge for both types of milk and I would like to politely request that you consider this policy also in Starbucks USA.

My friends at PETA are campaigning for this to happen and I have agreed to support them with the quote: “Sir Paul is asking Starbucks to end its surcharge on plant milks,” and I sincerely hope that for the future of the planet and animal welfare you are able to implement this policy.

Many thanks.

All the Best,

Sir Paul McCartney

PETA has been pushing for the adoption of vegan milks for a while, not only for animal welfare concerns but because of the environmental impact of cow’s milk versus alternatives. McCartney’s Got Back tour rolls through Seattle (aka Starbucks headquarters) in May — maybe he’ll have plant milks free of charge by then.