I was surprised that it was possible to prosecute faking admissions to colleges as a crime, but apparently you can.
https://en.wikipedia.org/wiki/2019_college_admissions_briber...
This would seem to be similar. Perhaps it can be prosecuted.
[1] https://www.justice.gov/usao-ma/investigations-college-admis...
The U.S. mail and wire fraud statutes are notoriously broad and on their face, seem to cover academic cheating services. Indeed, there is a precedent to this effect: United States v. International Term Papers, Inc., 477 F.2d 1277 (1973) [1]. However, I think it was overcome by the Supreme Court’s rejection of honest services fraud in 1987 [2]. While Congress reinstated the concept [3], the Supreme Court cut it down again in 2010, limiting it to bribery and kickbacks [4].
So that could explain why the newer online services haven’t been prosecuted federally. Several U.S. states have statutes explicitly dealing with this issue [5], but I suppose they are not being enforced for jurisdiction or resourcing reasons. Perhaps the newer legislation in Australia [6] and New Zealand [7] will be more effective.
[1] https://guides.law.fsu.edu/ld.php?content_id=4996427
[2] https://en.wikipedia.org/wiki/McNally_v._United_States
[3] https://www.law.cornell.edu/uscode/text/18/1346
[4] https://en.wikipedia.org/wiki/Skilling_v._United_States
[5] https://guides.law.fsu.edu/termpapermills/statutesandlegisla...
[6] https://www.legislation.gov.au/Details/C2020A00078
[7] https://www.legislation.govt.nz/act/public/1989/0080/latest/...