Sins of the Fathers Chapter 7: The Man Without Fear - S3-E7
Plot hole: They forgot Daredevil can sense when someone's lying, one of his powers. So, he should've known Spider-Man was telling him the truth about the computer disk.
Sins of the Fathers Chapter 7: The Man Without Fear - S3-E7
Continuity mistake: When talking with his father and Smythe, Richard Fisk's grey pants briefly turn into the same color as his suit jacket.
Sins of the Fathers Chapter 7: The Man Without Fear - S3-E7
Revealing mistake: During the fight with Kingpin recycled footage is used from Season 1 Episode 7 Doctor Octopus: Armed and Dangerous. It's obvious when you see the background looking like the warehouse along with Doc Ock's machine behind Spider-Man.
Answer: I believe it was just a way to try and show the suit is "oily" or reflective. It also helps define the character's features since otherwise, he'd just be a flat black color. It's similar to how the black suit Spidey had blue outlines. (I don't know why they chose a pink/red color... maybe because red is associated with power/fire/war, so it's a more "evil" color?)
TedStixon