It might not happen in a rural environment, but it can and does happen in towns and cities - albeit occasionally.
See under "Should I feed the foxes"
http://www.hastings.gov.uk/animal_nuisance/fox es.aspx
I think it depends on the surroundings, how many foxes, how much available food for them, how tame etc I live in a two story block of flats in a city that backs onto a park, and foxes are very frequent and confident. There are metal fire escape stairs leading up from the flats gardens to balconies of all the flats and the foxes have learnt (probably by neighbours throwing food out to them from their balconies) to climb the stairs in search of food scraps from BBQ's etc and they do sniff around my neighbours cat flap. They have even chased her cat up the two flights of stairs, although thankfully haven't actually followed it through the cat flap - yet!!! We used to have open bins but recently changed to lidded wheely bins so the foxes have lost a scavenge place. I guess hunger might have made them braver too - its only recently we have noticed them climbing the stairs. So,in answer to your question, its definitely possible!