Was surprised once when approaching EDDM, with those high quality weather-experts, to find a lot of CBs hanging over the place instead of the predicted CAVOK; first we had to hold for some time, then during the approach a new CB came up a bit too quickly, and we initiated a GA due to a speed-increase of 40 knots in 2 seconds. Glad we had some precautionary extra fuel on board, because due to the CBs we couldn't land instantly after the GA!
I personally think it is insane to go away with less than minimum, there is no reason to do so; even better: there are 100s of reasons to take a little bit extra on board, even when the weather is good!
I had a fight with a captain once because he wanted to leave with minimum fuel, and I had several arguments to take some more on board (weather, traffic situation, non-ideal alternate etc.). He had no reply to my arguments, only that he personally felt fine with minimum only. After 5 minutes of trying I got up and said that if he wanted to fly unsafely, I wouldn't join the party. Before I could leave the cockpit, the captain had already agreed to take some more fuel with us. And yes, when we got a straight in at destination and landed with 1000kgs more on board than necessary, the captain said "see I was right" about a 1000 times, but in the event of a GA or diversion, I would be the one who could say exactly the same.
Also: If you feel unsafe: LEAVE!! Try to convince your skipper with arguments, and if he doesn't listen, and has no valid arguments for himself, then GET OUT. There is no chief pilot who will punish you, if you don't want to leave with less (!) than the minimum calculated (and legal!) fuel.
P77