Because Google has more than a passing interest in how well you sleep, if they can prove that their search engine led to your purchase then they can pull down some funding from the retailer. We're talking about a $3 billion a year pay-check for Google here, so this isn't chicken feed.
Making a causal link between your search and your eventual purchase is relatively easy if allowed access to your browser - Google are adamant that the data they track does not include your personal information, so you can sleep tight on your new pillows, under your cosy duvet in the knowledge that you are an anonymous cash cow for them.
And don't forget that one of the pre-eminent browsers in use today is Google Chrome, so tracking that data should be a bit of a home run for these guys. Why do you think they give it away? As a non-scientific measure of how well used Chrome is, I've checked on my stats for this blog and in the 18 months or so since I started in earnest 34% of page hits have been via Chrome, just ahead of the old industry leader Internet Explorer.
Not everybody thinks Google are being entirely honest about how they use your data. Last year Google were fined over $22 million for allegedly by-passing security in Apple's Safari browser and it looks like a similar legal challenge is being launched in the UK, with the announcement being made, with deliberate irony, on Data Privacy Day yesterday. I discussed data Privacy Day last year on this blog here.
Using my unscientific measure I note that about 5% of page views have been via Safari, which sounds like this blog doesn't appeal to Apple readers as much as Apple sales would suggest - but then again, I do take the odd pop at Apple so maybe that's justified. I can't help it if Apple fans are thin skinned. The split between Google and Apple surfers according to StatCounter, a company that uses more than one blog to measure with, puts Chrome at over 36% and Safari at nearly 8% so my method isn't too unreliable it seems.
Of course, many iPad users will have Chrome loaded as well, so they'll be making it easier for Google to to get richer while they look for stuff. I don't have an issue with Google, or anyone else, making a living out of pointing me in the direction of data I'd struggle to find otherwise but I guess I'd like them to respect my privacy while they're at it.
I've said my bit. I'm going to sleep on it now.
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