As someone who keeps kosher, my problem with your restaurant analogy is that for my needs, reading a complicated list of ingredients and individually matching it to a complicated set of requirements is a lot harder than just having someone check once that it meets those requirements. My nut allergic friends can testify that just because the ingredients list says it doesn't have nuts doesn't mean there won't be hidden nuts. There are times when there's no substitute for actually vouching for and properly advertising accessibility.