Beags.....old Son....you are getting Senile in your old age.
The Blues display Six F-18's plus a C-130.
You may have forgotten it but the logistics required to cover a country that is about 3,000 miles across and over 1500 miles from top to bottom....not counting the short hop to Hawaii and Alaska, is just a wee bit larger than the UK.
Likewise when you have Front Line Fighter aircraft that have two huge After Burner equipped engines as compared to an obsolete single engine trainer....the fuel burn is slighter higher.
As you may recall....though from your post I doubt you will.....the USAF Thunderbirds replaced the F-4's with T-38's for a while due to cost issues. The Blues went from the F-4 to the A-4 about the same time for a while.
They too went the small Trainer route as has the Reds for so many decades.