This is great for online supermarket shopping.

This is a down-the-road consideration, but let's say this approach becomes wildly popular, pushing people who would have shopped in person online in order to get their easy vegan options. Do the environmental benefits of a new vegan outweigh the environmental costs of a new online supermarket shopper, order process, and deliveries?

It would just be difficult to have the rigor for multiple restrictions out the gate. All you need is a couple of gluten poisonings to upend the whole project. Strategically, starting with one restriction can help them stress test the model and build out from there with great evidence for additional investors.

To cut straight, you need to line up the ends. You can't put causes' impact side-by-side and cut straight across. They don't line up. 

For example, can you one-to-one animal and human welfare? No matter now you answer that, you're answering from a philosophical standpoint that you'd need to defend before comparing.