The biggest problem is that you NEVER know whether any study published is done this way or not.
Spoken like someone who has never actually read a scientific paper. Any paper I've seen will give you: (1) the historical context for why they are doing a study, (2) the assumptions made in doing the study, (3) details on the observational data and model used in completing the study, and (4) a RANGE of possible results. It is true that the media typically doesn't do a good job of reporting uncertainties, but don't accuse the scientists of sloppiness when you're completely unaware of what goes into a scientific paper.
"Someone's been mean to you! Tell me who it is, so I can punch him tastefully." -- Ralph Bakshi's Mighty Mouse