You'll notice that the patent was allowed to lapse. Looks as if the guy decided not to bother taking the application to a full patent – and this was just for the US. I used to joke that in the US you could patent a glass of water and I don't believe I was far off, having reviewed many hundreds in my time.
The fact that you can lodge an application proves nothing at all. Nor does being granted the final patent itself. Unless it's going to make you some money or protect your business while you cream off some profits from your invention while it is still novel and compelling, there's little point wasting your time and money, in which case you may as well put it in the public domain – so that others can't patent it.
There are innumerable companies that have outspent themselves paying for patents that have no chance of paying for themselves. Bear in mind that you need to patent your invention in every country that you think may be a potential market for it. The costs rapidly spiral and I've seen some ludicrous examples.
Ultimately, if somebody wants to copy your invention, it's just a matter of time.
One common reason for making lots of patent applications and taking them to full patent is to build up an IP portfolio. You need this is you want to get investors all hot and breathless about your new business idea ie if you are looking to liberate lots of money from them. The US seems to be particularly keen on that, although you'll see it wherever new business ideas and investors collide.
Murray