The point is that it's not worth a patent.

Maybe there is different version of the galaxy with a slider that more closely resembles the Apple version?

For mine, I just have to rub my thumb along anywhere on the screen to open it, and I can choose a special pattern if I want (I really don't trust that one to work).

How else would you open a screen without buttons? By tapping on it in a pattern? Or by rubbing it in a pattern? Tap-rub-tap just to avoid a patent?

Expensive. Touchscreen phones have few parts, less assembly, less testing... even if the hardware costs more, the design and labour surely costs less?