How meaningful are Lastminute.com registration numbers?

Letter from five year-old's dad asks

I would take lastminute.com subscriber numbers with a huge pinch of salt. My daughter Heather appears to be on their list as we found out when we got an email from them. She is five years old and has never visited that site. Neither has anyone else in our family -- the only place this email address has ever existed was on my personal web site (not updated since 1996), on which I added her address. I was very surprised to hear that Heather had been so interested in lastminute.com. I don't know who they bought their database from, but it is more than a little suspect! Needless to say, I shall not be visiting a site that would spam my own daughter before she even learns to use email. ® Email and web site addresses supplied.

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