Considering that the author likes the idea of carrying his stuff in a brown paper bag. I don't think a beat up looking laptop would bother him. In fact, if you look at the picture, there are a few scratches and dings on his laptop.
Minor scratches won't affect functionality in any way, in fact, I think there is a certain beauty to it. A laptop is a tool, a tool is meant to be used, and usage leaves marks. If it looks spotless, it is as if no work has been done on it.
I‘m fairly sure that generation of MBP is USB-C only. If a UK plug prong is smashing its way in there, you‘ve got much bigger problems than a shorted port.
Minor scratches won't affect functionality in any way, in fact, I think there is a certain beauty to it. A laptop is a tool, a tool is meant to be used, and usage leaves marks. If it looks spotless, it is as if no work has been done on it.