Countries like the UK weaponize aid. It's not simple charity, it is another means by which to exert power. You can see it right now with the defunding of UNRWA, the blockade of Gaza, sitting by while Israel blocks aid. It is part of a pressure campaign.
It also acts as PR.
As Thomas Sankara said, "he who feeds you, controls you".
This is why Western powers react negatively when other countries seek food sovereignty.