When Procter & Gamble put the squeeze on a start-up toothpaste firm, the company's founder was all smiles. “Thanks P&G,” said Craig Dubitsky. “They’re accelerating and amplifying our marketing efforts.” Dubitsky uttered those words after P&G won a legal fight with Hello Products LLC to stop sales of its toothpaste.   For nearly a year, P&G has been arguing that Hello’s labels saying the toothpaste was “99% Natural” were false and misleading. In April, P&G c...