The horse joke was a reference to the massive recall a decade ago, when they found horse meat in their balls and sausages.

Also, as a non vegan, I find the veg balls to be as good as their meat ¯⁠\⁠_⁠(⁠ツ⁠)⁠_⁠/⁠¯ As long as one doesn’t expect it to taste anything like meat…