There are a few reasons. First, it suggests a preparation that is reminiscent of a food that people enjoyed before they stopped eating animal products. This me

There are a few reasons. First, it suggests a preparation that is reminiscent of a food that people enjoyed before they stopped eating animal products. This means that the spices and texture will be similar. That's an indication for both vegetarians and non-vegetarians to expect a texture, condiment, and spice experience. Second, it's not about disguising foods as other things; it's about combining foods. Falafel isn't fake meat, but it's ground chickpea (or fava bean in some cases) flour. Meatballs aren't somehow lesser because it's ground meat, no? As such, the thought of ground beans or other combinations into patties isn't somehow any more deceptive or disguised as ground meat. We transform food in all sorts of novel ways - that doesn't mean it's disguised because it is a substitute for other purposes. Third, while vegans eat a lot of vegetables and mushrooms and beans, most people don't want every meal to be that. We crave variety in general, and a lot of plated vegetable plates are out of place at a barbecue or restaurant. So, it helps when things look in place.