... BUT you say it takes another TWO HOURS to brew the same 5 gallon batch in AG vs extract ??
I think it very much depends on exactly how you brew - there are lots of variations. For instance, a friend of mine brews using the "fly sparging" method, whereby the sparge is accomplished by continuously draining the mash while adding water in the top at the same rate, until the runoff gets to a certain pH level. Actually, I think he's been doing it so long he doesn't bother testing it, he just goes for a specific volume, and then boils down to his target. At any rate, he spends all day brewing. He says he starts around 8 in the morning to finish by 6pm. OTOH, I find my brew day consumes about 5 hours start to finish (including cleanup). I batch-sparge, so the sparge itself doesn't take a lot of time.
One part of AG brewing DOES take more time than extract: the mash. If you're brewing with extracts, you basically pick up the AG brew day after the mash is drained and sparged (i.e. that's where an AG brewer's extract comes from), so any time prior to the boil would be in addition to the extract-brewing experience. Basically that 2-hour "premium" is the time it takes to heat the strike water, plus the time to mash and sparge (batch sparging, that is). I find it's worth it, since even when I was extract brewing, a brew-day would take up most of the afternoon, by the time I measured everything, got the water heated up, did the boil, etc. Plus, at that time, I was brewing indoors, and the family was complaining about the, um, aroma.
One thing, I'm curious about your comment re: sugars. Do you mean sugar added to the wort, either during or after the boil, or are you referring to priming?
Tim