Shirayim is something you can take or leave (we don’t have it in my Chassidus and I never went to a tish where a Rebbe gave them out though I probably would if time ever permits me to do so). You either go to the tish to get it – or you don’t. You either hold by Rebbe Aleph or Beis – or by Gimmel – or by no one. All is well and I fully do understand those who have no interest in shirayim. It certainly does not compare to superstitions except if you misunderstand them and the role of a Rebbe who may give them out.
If you think chapping shirayim will cure illness, and you use it instead of medicine, then yes, by all means it belongs in that category and if you tell people to go to get them for that reason, you are a dangerous fool.
I purposely used some wine I got from my Rebbe years ago to rid myself of a skin infection that I noticed one night – and as I expected, it did not work. The cream I picked up the next morning did the job. My Rebbe would have told me on no uncertain terms to <b>cut it out</b> if he had been with us at the time and I had written him to tell him it did work and that I was going to hand it out to others. If I had arak from Baba Sali – or from Nissim SuperZol in Machane Yehuda – it probably would have worked because arak has mild antibacterial properties and wine does not. If your reason for shirayim is based on Chassidus, and therefore far more than I can explain al regel achas, then it is not in that category at all. And if you have no interest – don’t go – it is not a doraisa!
Baba Sali ZYA himself said that if you truly believe in Hashem and His infinite power you don’t need his water for a brocho – ordinary tap water will do.