As you'd expect, this swarm of simpletons was pretty disruptive to the whole "peacefully laying eggs" thing, and some of the turtles returned to the sea without dropping off their prenatal payload. As a local official said to the Costa Rican news outlet La Nacion, "That certainly is a negative impact."
Why wasn't the area protected, if it was on a wildlife refuge? Well, it actually was: park rangers (and even the police) attempted to put a stop to the madness, but because the crowd was so massive, they weren't able to re-establish order before the damage was done.
Pro tip: if you're visiting Costa Rica, maybe just stay the fuck away from the sea turtles.