Hell, you don't have to look past 'Alien' to find a similar behavior - Dallas knowingly broke quarantine not even knowing if they could save Cane and risked killing everyone in the process (which actually fucking happened!!)
Once again a ship full of space miners != a ship full of supposedly genius-level scientists.
Nope - doesn't wash with me. There were quarantine laws that were clearly known by all on board Ripley's ship. I'm not a scientist but I know the dangers of pathogens and viruses and the reasons for quarantine. All of it sounds like lame justification for peoples' blatant inconsisteny in hating on one scene and not on the other. The real reason is that Alien overall was a far better movie and thus worth closing a blind eye to its own logical fallacies.
“The greatness of a nation and its moral progress can be judged by the way its animals are treated.” - Mahatma Gandhi