Vegan businesses are absolutely a potential ally. Not sure what lifestyleist businesses you're referring to. I think the biggest one to really figure out is businesses that people feel help them personally. This is why the far right are targeting self-improvement. They are tying people's personal growth and genuinely felt changes in their material conditions to the fascist movement. The Vegan businesses have a potential role to play in that for the left, people that do make those transitions do genuinely feel a sense of personal accomplishment for having done so and find a sense of community in support and help that exists to make the transition.
I think a major aspect of this is that it's sustainable radicalisation. Once you have a business embedded in a community doing this it really isn't going anywhere if it's making money. This is why pods and streams have been so beneficial too, but they only exist in the digital space there's the physical community footholds to organise around have their own uses.