They had 317,000 £ so either <PERSON> is secretly rich, she stole from her parent's accounts, or someone else prepared cash while <PERSON> thought the reader assumed it. They have to be in the wildernes most of the time on the run and all that. However they wern't adverse to goign to town and buying food they did it for a special occation (I don't remember what) but the stupid tihng is that they never thought to kep buying food.
OK so summary of what she was thinking is that they weren't going to be driven out of Grimmauld Place. So she decides to bring what was needed for thier infiltration. The book never mentions thier escape plan, I'm assuming whatever it was doesn't work once caught. They were NOT in the same position as a resistance, their situation is more liek real life fugitives. She also probably brough tea probably to relax themselves in a tense situation after done (or maybe inside the raid if the people who thought they were subordinates were on break) and in th wilderness it doubled as heat and hydration and YES British sterotypes. Note the North Irish and people who live in historical ulster not part of UK consume 30 times as much tea as other parts of the EU, nearly as much as the english despite the northern irish not considering themselves British.
As for the cheap excuse to make everyone hungry, yes but again consider they didn't think about being busted. Also people tend to forget about food when being fed by someone. So remembering to bring tea and not food is not out of the ordinary. 45
One might wonder why they had so much cash if they were so short sighted. It's easy to assume someone DID go to the bank off page for some spending money that afternoon and just hit "zero" too many times. As I mentioned they DID buy food at one ponint. However it was a small shop possibly family owned. These tend not to have a lot of preservable foods like canned food, at least in my coutnry. I think going to buy food more than once a week, even at different stores, is going into settled areas way too often considering that would look like vagrants who just happen to look like wanted people. Without access to refidgeration, there isn't much from the smaller shops that won't perish too quickly. One could argue that after they bought food once they could consider buying food every week to relieve their foraging presssure. I... don't really have a rebuttal to that. Maybe they just didn't have enough time to think? 121