As on a regular basis I receive these sms' from all kinds of businesses. As an example I received three over a period of two days from Woolworths and I do not even have an account with them. I am waiting for the next one and then I will send them an email asking them to stop harassing me.
A day or so ago I received another from some insurance company followed by a phone call about half hour ago. I questioned them as to where they got my information from. They claimed that they get their information from a company called "iData". I am certain that whomever it is would not give such information out for free. Is it not illegal to be contacted by a company trying to sell you something if you did not give permission to be contacted by sms?
I know that you are always given the option to opt out, but you have to pay for that sms. I think everybody with a cellphone experiences this and sometimes at even inconvenient times.