Of course there are some negative consequences of selling fossils in the commercial market, but they have been greatly exaggerated.
The benefits of commercial fossil trade greatly outweigh the disadvantages.
First of all, the public is likely to have greater exposure to fossils as a result of commercial fossil trade, not less exposure.
Commercial fossil hunting makes a lot of fossils available for purchase, and as a result, even low-level public institutions like public schools and libraries can now routinely buy interesting fossils and display them for the public.
As for the idea that scientists will lose access to really important fossils, that's not realistic either.
Before anyone can put a value on a fossil, it needs to be scientifically identified, right?
Well, the only people who can identify fossils, who can really tell what a given fossil is or isn't, are scientists, by performing detailed examinations and tests on the fossils themselves.
So even if a fossil is destined to go to a private collector, it has to pass through the hands of scientific experts first.
This way, the scientific community is not going to miss out on anything important that's out there.
Finally, whatever damage commercial fossil collectors sometimes do, if it weren't for them, many fossils would simply go undiscovered because there aren't that many fossil collecting operations that are run by universities and other scientific institutions.
Isn't it better for science to at least have more fossils being found even if we don't have all the scientific data we'd like to have about their location and surroundings than it is to have many fossils go completely undiscovered?