After the dry summer when it was probably difficult for them to dig up worms and find slugs, which are a main source of their diet, they are probably desperate to fatten up now before their winter hibernation. It's a myth that they like bread and milk as they're definitely not vegetarians, but they will eat it if they're desperate for food. However, if you put out some tinned cat food (meat varieties, not fish) they will be very grateful and you could be helping it to build up enough fat reserves to survive through its winter hibernation.