I guess they felt the blue wire was a thinner gauge and it would melt (like a fuse) before anything else did....
But, thats not the case. The blue wire looks to be larger than 16 gauge which carries 15 amps but it's not designed to fail like the one Mike posted.
I had a quad here awhile ago, he had a 30 or so amp fuse in there, it called for 15. I said "why did you use such a large fuse?" he said "it kept blowing"
I explained that when stock fuses blow, there is an issue somewhere that has to be fixed.
You can use any fuse holder you wish as long as it's the proper amperage and in your 1st pic, covered in electrical tape!
All our government does is distract us while they steal from us, misspend our tax $ and ruin our country