I've just read the article again. These people are even bigger morons than I thought.
The inbound from Nimes arrives at 12.15 - assuming it's on time; and the pax were booked on a flight leaving at 12:45. As FR close their check-in 30 minutes prior to departure, there's absolutely no chance that they could have made the second flight!
All the more so since - again as it says very clearly on the website (in French as well!) - pax connecting with other flights will have to collect their luggage on arrival, go through customs and recheck them. I believe it says there that at least 90 minutes should be allowed for connecting flights.
Unfortunately, this is a perfect example of your average low cost airline pax.