On boards over 6" that I need the extra width on I can usually get it flat enough to run the planer on my jointer. I remove the guard and take light cuts where needed. It is not an ideal situation, but it works well and doesn't take much longer than usual.
If you want the 8" model I say go for it, but I personally would save that money and use it somewhere else as Kev has said.
You can also rough out your parts first and then mill.
There are times when you want boards of that width tho, I agree. But, frankly, the bulk of most hobby shop projects don't use boards that wide. Again, just a cost to return ratio.
Oh, I see. True, it is quite a difference between the cost of a 6 or 8" jointer. On the other hand, unless it's an exotic, I seldom buy lumber that isn't at least 6" wide. I know I can rip it all to 5 1/2" and run it over the jointer, but that seems like a hassle. It's funny...The cheap Jet combo machine I have is very frustrating, but with it being 10" capacity the width of my stock hasn't even entered into the equation.
Yes I have a Steelex 10" bandsaw which isn't wonderful but I got it tuned to track well and it will resaw if I take it slow and easy. I also have a $100 benchtop Craftsman which I keep a 1/4" blade on for small curved work.