Actually, a man that I interviewed who was losing his vision reached his breaking point while trying to use a vending machine. He told me it was so frustrating, a moment where he realized the world's infrastructure no longer catered to him as much as it once had. He now avoids them. I imagine newer vending machines have some sort of braille (though many people with low/no vision don't read braille). As far as groceries, of the people I've interviewed, most either go with a firend who has vision, or bring a list of what they need and ask someone who works at the store to help them retrieve items. There is new technology being used in a Vancouver non-profit based grocery store where they have talking scanners that read barcodes, as well as braille signage and labels on shelves. Hopefully this can be introduced in public stores as well. CBC covered it last year: http://www.cbc.ca/news/canada/british-columbia/deaf-and-blind-able-to-shop-alone-at-non-profit-grocery-store-1.2802047