That’s simply not the law. You might wish it to be the case and might advocate for the change in the law, but it isn’t the settled law as of the moment nor of the past 200 years.
See eg; United States v. Jacobsen, 466 U.S. 109, 113 (1984); The right of the people to be free from unreasonable searches and seizures proscribes only governmental action; it is wholly inapplicable “to a search or seizure, even an unreasonable one, effected by a private individual not acting as an agent of the Government . . .” Walter v. United States, 477 U.S. 649, 662 (1980).
See also: See, e.g., United States v. Hall, 142 F.3d 988, 993 (7th Cir. 1998); United States v. Barth, 26 F. Supp. 2d 929, 932-35 (W.D. Tex. 1998); Commonwealth v. Sodomsky, 2007 PA Super. 369, 939 A.2d 363, 368; People v. Phillips, 805 N.E.2d 667, 673-74 (Ill. App. 2004); United States v. Hall, 142 F.3d 988, 993 (7th Cir. 1998); State v. Horton, 962 So.2d 459, 463-464 (La. App. 2007).
Like I said lawyers will be along any second citing court cases to the contrary and the reality is these cases prove very little if anything.
United States v. Jacobsen has virtually no bearing on this discussion at all and determined only that in this particular case the private party did not violate the fourth amendment. That has nothing to do with the issue we are talking about and the case simply isn't relevant and the decision does not apply.
The question is can a private entity perform the acts of and conduct itself with the authority of government and the answer to that question is absolutely not. A private entity cannot levy taxes, cannot arrest someone, cannot prosecute someone, cannot jail someone and the can't search anyone or anyone's property. Those are all the functions of government and government in the US must be ratified by the people and then must conduct itself in a Constitutional manner which makes random arbitrary searches illegal. The question that must be asked to determine if searches by private businesses are legal is simple. Is this entity government or not government. If the answer is not government then they cannot conduct themselves as such. This is where the line is drawn.
This can be seen by my extreme test where a private entity decides they are going to do strip searches for patrons who have paid to enter the venue. Anyone can see that would not fly. Then one would ask what about electronic searches? We have technology today that can see right through peoples clothes as used at airports on a limited basis. Could Home depot use this technology? Of course not. So where is the line? The answer is Home Depot can't do any searches because they are not part of our ratified government.