Language is constantly evolving.
I assume they just don’t notice the difference, like with marry/merry/Mary.
Wikipedia agrees that this is common: "In North America it is often pronounced with a short vowel sound /krɛɡ/, as in "egg"" [1]
Not the same thing at all. This is more like someone following different pronunciation rules insisting that your name as spelled is pronounce "Kee-lay"; and if you actually want "Kaa-il", you should spell it K-A-I-L instead. It kind of makes sense that way too, as long as the rules are somewhat consistent in their version.
If the creator wanted to name it after Jif, the extension and name should have both been JIF. Putting in a G instead of a J is begging to create confusion about the pronunciation.
Are you from Wales?