People are spending less at restaurants -- and it's ominous news for the economy

Andrew Burton/Getty Images The restaurant industry is providing some ominous insight into how Americans are feeling about the economy. Restaurant sales are virtually flat, and they're expected to remain weak for the rest of the year, according to The NPD Group, an industry research firm. Weak growth in the restaurant industry is a warning sign for the entire economy, Nomura analyst Mark Kalinowski told Business Insider. People need to eat, and when they pull back on restaurant spending, it's a c...