...but then everybody would be expecting the webserver (and probably Linux in general) to accept .jpG .jPg .Jpg .JPg .JpG .jPG as well as the same combinations for every other file extension out there
You can hardly be sillier in your answer.
Parent poster already explained that some camera's throw out IMG1234.JPG files. Upper case that is.
My Pentax does that as well.
You are not telling me they aren't images just because you proclaim JPG to be an invalid extension. The latter is a neo-UNIX-newbie's typical pitfal.
If I want JPG's to be image files (for all I care they could be read right from the SD-card) and the 'system' doesn't provide for it, the system
has a shortcoming that needs to be fixed.
Typically under UNIX we make a fix a flexible one: allow the user --who came to UNIX for that power and to be treated as an informed conscious
adult that knows what she wants--, allow the user I repeat for instance to add a string to a plain text file listing extensions for images to be recognized.
What list?, where? -- that's something the person that broke this should know.