Although the Reds total cost to the MOD balance sheet is very small indeed - they may be disbanded, but an awful lot else will have to go as well to achieve the new saving target.
To my mind, the main problem caused by the Reds continuing to exist is not that they cost a lot of money which could be put to better use elsewhere, but that the existence of a full-time display team who put up a large formation of brightly-painted jets suggests to the public that the RAF/MOD can't really be that short of money or else we wouldn't have this 'extravagance'. The revenue which the Reds bring in, directly and indirectly, is largely overlooked.