Logical marketing?

Some time ago I purchased an HP Windows laptop, yes I am aware I don’t like Windows, but it was purchased for a specific task which is to program radios, and it does that task very well.

When I purchased it I registered the machine on the HP website agreeing in the progress for them to send me details of updates and other products. I mean I could always delete unread if I was in the mood, and perhaps they would send me something of interest. A few weeks later I sent them feedback that I was happy with the laptop.

Now the above is straightforward and easily understood, this being the case why, every few weeks do they send me emails advertising new shiny laptops? Blimey the one I have is not twelve months old. Do they expect me to be so unhappy with my purchase that I would want to upgrade it? If this was the case do they think that somebody so quickly unhappy with their purchase would want to purchase another of the same brand?

In all the years working in retail and running my own business I never got my head round the logic used by professionals in marketing.

Now the real question is suppose is the one that asks if my experience above is unique, what are your experiences?

Answers in the comments please.