Gaining popularity I mean, but its a no veggie dietThats not a new trend. That is what their diet actually should be.
Hay is grass. Grass is hay. Many different varieties of grass/hay and not all grass makes a good hay but this is what rabbits need.
Some grasses do lack nutrients depending on where/how they are grown. Like places where the dirt is just dead. So thats where supplementing with pellets/veggies come in.
I would most likely grow grass, so then I could get many different typesI think that a grass diet wouldn't be bad for a rabbit, but you would need LOTS of fresh grass because the grass would take the place of the veggies. Also, I would be nervous to feed my rabbit grass with RHDV spreading. You would also need to provide your rabbit with a salt lick to allow the rabbit to get the nutrients it needs.
I think that if you are feeding Peanut a variety of grass hays, veggies, and a high-quality timothy-based pellet there is no reason to change his diet to something that is new and still being experimented with. Stick to something that we all know to be safe, instead of playing with something where you are unsure of the outcome.