I don’t think the “The Parking Garage” (one of two Seinfeld choices) was even in the top 30 of my favorite Seinfeld episodes. I forget which of the 1950’s horror shows (The Twilight Zone, etc.) it was on, but “The Hitchhiker” episode was my all-time favorite in that genre. A young woman driving from New York to California keeps seeing the same old man hitchhiking all the way across the country.
IIRC, the parking garage episode was probably included because it was cited by the cast members as the one that made the show about "nothing" and gave them the courage to do entire episodes about waiting in line at a restaurant, etc.
BTW, Seinfeld wasn't really about "nothing." It was about where comedians get their material. Bonus note: at the end, the car really didn't start. That wasn't planned.