The Placebo Effect should be the difference between No Treatment and Sham Treatment for an identified problem. One could also consider an Ignorance Treatment where patients are asymptomatic, and a Denial Treatment, where you just tell the patient "it's nothing, don't worry about it".

I believe studies have been able to show a statistically significant outcomes between Placebo Treatment and No Treatment.

I'm personally quite annoyed with knee jerk "that's just placebo" claims, which then go on to claim that if a certain statistic of a certain treatment regime for a certain substance on a certain population didn't pass some statistical significance test relative to a sham treatment, then the substance "has no effect", etc.

So I don't think the problem is that Sham Treatments have no statistically significant effect on outcome, but that people leap to unwarranted conclusions from failures to reject null hypotheses.