To repeat, it's not a collision, because it was not accidental. Kimball and Mattis named their image editor after the full-body sex-slave suit, on purpose. GIMP is a backronym.
It's also worth emphasizing that "Pulp Fiction" is not an obscure movie, it was actually a very very popular movie from the 1990s and it's still relevant today. It won awards from every organization that gave movies awards. It was recently quoted by the US Secretary of Defense during a prayer, who thought he was quoting the Bible.
While I believe you when you say you're personally not familiar with the usage of the word, it's a word that you can expect most people would recognize.
Ask anyone under fifty what "pulp fiction" was and prepare to get mostly blank stares. Can barely remember it myself.
Reminds me of those creeps in "Footloose" trying to outlaw dancing. Puritanism can get fucked. ;-)
Do you have any evidence it was done on purpose? The devs have referenced the unfortunate name a few times but I think it is infinitely more likely they chose the name in reference to the poor quality of the software or as a normal acronym