One of the arguments that is regularly advanced in order to justify why the right (and therefore the power) to carry out archaeological fieldwork should be left to professional, archaeologists who have a degree, is that there are no amateur surgeons or amateur policemen either. Leaving aside the fact that this is simply not true, this bon mot says more about how some archaeologists understand science and society than it does about the needs of archaeology or heritage protection. It is simply a case of who has the power to decide what happens or not happens in archaeology. It has very little to do with what is "good" for archaeology and its purported "owner", the "general public".
This argument is one of the dirtiest "arguments" put forward as part of an "authorized discourse on heritage protection" (to use a term coined by Laurajane Smith), which we archaeologists largely pursue in a dishonest manner, to normalize "our" dominant position: it plays on existential fears of our conversational partner in order to conceal that, by doing so, we take away fundamental civil rights from them. We even try to convince these people that this deprivation of rights is reasonable or even necessary. The suggestion is that they should be grateful for this deprivation, as it is in their own best interest, since the transfer of "archaeological" power seemingly is for their own good. This argument shows that many of us have failed to understand why civil rights as a whole are of fundamental importance, including certain civil rights which are fundamental for ourselves as academics, and that they are indispensable in order to maintain a social order in which we can freely pursue our scientific interests.