when you accelerate, the wheels turn forward, but as long as there is grip on the road, there is a counter force pushing the car toward the trunk. You see it clearly in muscle cars (think Vin Diesel in Fast & Furious) where the front 2 wheels lift off the ground. Since VW golfs are front wheel drive, the counter force will never lift the front wheels up. Instead, the front stays planted on the ground and the trunk sinks down a little.
I can see this clearly when I drive at night and from a stop light, my headlights angle up a little when I accelerate from a red light and then drop back down. It's probably 5-10 degrees but very noticeable when you look for it. If the rear wheels are taller and the springs/struts are not corrected, the weight balance will put additional stress on the rear struts/springs each time you accelerate. It will most likely lead to premature wear. I snapped a 25mm upgraded sway bar from the extra stress when I went taller on the rears.
I recommend getting taller tire on all 4 wheels