Rod
Contrary to some members feelings about foxes, I am FORTUNATE enough to have a fox regularly visiting the back garden. He lives next door I think. This fox is stunning with chocolate tips on his feet and tail and boasts a healthy thick winter coat. I have put food out but only intermittently because I don't want to create dependance - which I suspect is the thinking behind your question. I came home from work this morning (work nights) my view from the train journey included Herons, Kestrels, saw a Jay was outside the Station then arrived home to see the fox in my Garden - What a great end to a boring night shift at work! - sadly, was totally unprepared, end of film' in my SLR and batteries flat in Digital!!
As far as foxes being 'vermin', I don't keep chickens, cats (I wish he'd eat the neighbour's 3

) or have any other interest which conflicts with his presence. As far as raiding the rubbish, a pair of rubber gloves, a bin liner and 10 minutes of my time is a small price to pay for the privillege of such bio-diversity in a truly urban Victorian garden.
I would feed any animal that looked dangerously mal nourished but as I said, I would be really wary of creating dependance and I would be reticent to put high sugar content food out as this rots the teeth and could cause metabolism problems. Our urban foxes somehow seem to thrive, Baby seagulls are their favourite diet around here (another type of 'vermin' according to some!) but not many around in December!
Deborah