Since we're going flag, 121.621 doesn't have a however, if is a " must list at least one alternate unless..." So minor distinction in grammar. But the problem I really have is once we add the alternate, the strong majority of out pilots seems to believe they have to land with X amount at the alternate. So now we are more fuel on top of alternate burn because the crew believes they must land with 75 minutes of fuel in the tanks at the alternate. In the case above, there's the potential that you've doubled the fuel at landing for "comfort". Since I've been taught safe, legal, and economical (in that order) is my job. Just doing my job
All that said, I think there is a "comfort" factor, but just using the word comfort doesn't mean you shouldn't have a good solid factual reasoning behind it. There are certain unique challenges that happen and specific places the crews may be aware of and I'm not. But you should be able to explain that and not just say "I'm uncomfortable".
No where in my job description does it say I'm expected or required to get a captain off.
It doesn't have to be regular service to use flag rules. We do lots of charters/repos between C70 airports released under domestic/flag rules (as appropriate). The OP, according to profile, is a cargo person. We tend to do a lot more point to point outside the US. Both FDX and UPS have extensive inter region networks, similar to old days of pax service when United and Northwest had extensive NRT hubs or Pan Ams Frankfurt hub ops.
And then if you just start appeasing captains, the next one wants an alternate, then the next, and then the next one wants an alternate plus 60 minutes. Before you know, you've given up Czechoslovakia to Hitler in the name of appeasement, and we know how that turned out!