No there isn't. People are just curious because they like what they hear. Hence posting questions in the "strings" forum.
Some strings are brighter than others, some have more flexibility, some more or less tension than others. They have lots of tonal nuances. Specifically, these are things that asking questions about strings is good for. I'm not trying to poo-poo the OP here, just saying that you can use literally any kind of string you want with disco music. Some people play flats and some rounds. For the most part, disco lines have been recorded with roundwounds. Back in those days, there weren't as many brands as we have now. There's a good chance at least half the bass lines were recorded using Rotosound swing bass strings.