While I was enjoying one of my favourite food Hokkien Mee, the owner came over and asked for my contact number. She says that they might be moving to another location and would like to keep me informed. I thought that was a brilliant idea and gave her my number. It might sound as if I just allowed someone to spam my phone but that isn't the case. She specifically asked for my permission to keep me informed about something I'm obviously interested in. Assuming she keep her end of the deal by not spamming me with unrelated stuff, this is a win win situation.
Traditional marketing approaches like advertising tries to interrupt as many people as possible. A better approach would be Permission marketing (a term coined by Seth Godin) which focus on building your permission base first before marketing to them.
This approach feels more personal for the customer and also more efficient for the marketer since they are marketing directly to someone who are interested in their product. And once you have a group of people who are willing to listen to you, you will have a better chance to turn them to a regular and loyal customer.
If you are running a business, writing a blog or starting a group, ask your prospective targets for their permission first before spamming them. They'll thank you and might actually listen to what you have to say.