Please, Don't Call

I was at Honeybaked Ham Saturday and the cashier asked for my phone number. I was paying cash yet she asked for a phone number. Even if I wasn't paying cash, what's with the phone number request? I was buying ham! Ham! Why would my telephone number be needed to buy ham slices? I assume the fine folks at Honeybaked wanted to put me on some kind of list where I'll start to receive unsolicited calls about...wait for it...ham! That's the last thing I want or need. It's bad enough I get emails I don't want, but unwanted phone calls are an entirely different ball of wax. My father, whenever he gets asked for his phone number, gives a fake number. "Yes, you can have my number," he'll say. "It's 334-555-5555." I'm too lazy to put forth that kind of effort, so I just refuse to give a number. That usually does the trick. What's surprising is the number of people who just freely give their phone number when asked. The guy ahead of me in line gave his number without any hesitation. Did he think he wouldn't be able to complete his purchase if he didn't comply with their request for information? Wasn't he aware he could simply refuse? Or maybe he likes the idea of possibly being contacted by phone about specials on ham and other assorted Honeybaked items. I understand some stores that request information like your zip code for tracking purposes to see where their customer base is coming from and I have no problem giving my zip. But why is my phone number needed? I don't even have a local phone number. I haven't had a land line in close to ten years so no helpful demographic information would be gained by tracking my cell number.