I have fat dumb fingers this morning!
OK, I may be able to finish this!
You will have a LOT less rolling resistance on the highway, which equals faster speeds. You will have a LOT less frontal wind drag on the tires, yes, it makes a difference on the Sammy. They will be lighter, faster acceleration and stopping, to some degree.
Off road is the test for many. There is a whole science/debate on fat vs. skinny tires. But skinny tires will offer more pounds per square inch surface pressure and contact. You need that for tire adhesion on the road or trail surface. Good on ice. Fat tires will offer a lot less surface pressure even though it will have a larger surface area. That is opposite of what you generally need.
Aired down to about 4-5 PSI you will have a long narrow contact surface so you are not pushing the dirt, sand, mud or whatever that a fat tire would. A skinny tire will dig down in slushy or muddy conditions. All bets are off in REALY deep mud. I sank almost to the front bumper this winter in deep mud!
Skinny tires aired down will tend to wrap around rocks instead ridding on top of them, better for rocky climbs.
Last of all, almost all deep exploration vehicles use a skinny tire.
Almost last of all, they don't look all macho and bad! Your choice, look cool, or have the ability to wheel in tough conditions.
Macho tires have their pluses too, but when mine wear out I am sticking with the skinny ones.
