summary: the holes are almost never (purposely) used to secure the plug in the socket. it is often just for manufacturing reasons (but not always, as in this case). it is included in the specifications as an optional feature, so that the holes are not made too big, or in the wrong place.
the perspective makes the text appear shorter, while staying the same width, which gives it normal text proportions. its hard to read when stretched out because your brain has to follow thin lines (next to each other) to form letters