It’s all about sharing information these days; online, on social media, and with stores where you shop. Some stores offer you rewards for letting them add your phone number to their customer registry. It’s best to forego the special deals and keep your number to yourself. The same is true for any business that you deal with which doesn’t require your phone number. Businesses often sell phone numbers to third parties. The more you give your number out, the more likely it is to land in the hands of scammers.