How do you know your screen looks no different? You haven't seen mine! LOL
I did actually look at some benchmarks out of curiosity to how 2 x 7800GT compared to 1 x 7800GTX and really the SLI setup only beat the single card by a few framerates.
Yeah but benchmarks are over rated anyway, they mean nothing, think about it unless your system is exactly the same as that they benched then you won't see numbers even close. And also reading a benchmark or review on a item at a site that also advertises for the same they test are most cetain to write a biased review.
As said earlier you must physically see it to belive it, a web page and some bar graphs mean nothing. and by a few FPS means 30-50 FPS on some games and more on others then yes sLI is a "little" better

Saying a 7800GT is 300-350$ two of those is 600 -700$. A single 7800GTX is 450- 500$ A few extra frames for 100 - 200 extra..
And saying that you will be spending maybe $150 less for one 7800 GTX than for 2 7800 GTs, doesn't make much sense, since the GTX is the same thing as the GT just that it is factory overclocked, something you can easily do with the GT and then some
So why pay more money for one card when you can get two and overclock them more than the GTX ?
SLI in my view is like having dual cpus, in desktop that other cpu is prolly used about 5% of the time.
You obviously have been mis informed on more than video cards, think of it like this,
You running a hungry application, basically any newer pc game for example, or flight sim take your pick, what do you think will give better performance? a one lane highway for all the traffic to flow on or a multi-lane highway?
Obviously the highway with more lanes will have traffic moving faster, the same works with dual core and sLI, you aren't limited to the flow of one lane.
With the dual core processor the workload is divided evenly between both cores, same goes with the sLI , if you can find someone with a dual core and sLI setup and take a close look at it, reading benchmarks won't allow you to see the benefits and it isnt all about frames

there is a lot more than just frames that come out of a setup like this.
Performance, speed etc is all part of it not just a frame rate number
