540 mp 180 fuel is hardly "cheap".
the panther is 490 mp 175 fuel and it's known for being rather pricey. the wehr panther might be behind a stack of tech unlock, but in the preview the OKW panther is rather easy to access.
(not that I think okw panther is too easy to access.)
its cheap considering the fact that you dont need to spend that much fuel as brits. you can maintain map control with LMG sections and AT guns, and getting medium tanks is actually pretty unnecessary thanks to the fact that the sections are superior to axis infantry. in 1v1s and 2v2s however its a lot more likely to get comets, but ive managed to pull off 12-13 minute churchill timings with manpower/munition only builds in 2v2s thanks to the efficiency of sections/vickers/ATguns. youll never see that kind of timing on a panther.
crocodiles are even better because you dont even need to tech, rather just wait for the CPs. so if youre on the backfoot you can save fuel for a 180 fuel tank that has arguably better AI than a KT. in addition often times the time it takes for an enemy player to take out a crocodile is equal to the time it takes for you to get another 180 fuel.
if you look at the costs on their own, yes, its not that 'cheap' but when you look at the cost in the context of the faction, it is not that high of a price.