Agreed, in a strange way, it's almost encouraging people to travel when they might not have been sure. If they were going to an event that is cancelled this might provide them with no reason to go, but if they were planning a weekend in London to see a range of things that are still possible (but strongly advised against) then not allowing these refunds might encourage them to make the trip, potentially causing accelerated spread of the virus. It's a bit of an extreme view perhaps, but if we are strongly advised (with potential for that to be stepped up further) not to travel by the government then everyone should do their part to discourage it. Can the government not pay the retailers fees?