Anonymous is asking individuals to pro-actively take food to those without shelter.
This isn't a charity donation scheme with a central accounting house. No representative is demanding money. The concept is much more simple than that.
While some members of the movement are organizing soup kitchens, the call is for quieter action.
There is a press release, which spells it all out. The pertinent passage reads:
Every Saturday we are reaching into our own pockets and giving away food to the less fortunate. Some of us will be feeding hundreds of people each week, but you only need to give away a single apple to join the cause.
This is followed with a request - not a requirement - that anyone participating does try to record it in some way. It could be a photograph, a blog, a Tweet or film footage. The recommendation is to do it anonymously, perhaps donning the famous Guy Fawkes mask, as this should not be a platform for personal recognition nor gain.
The object is to get the message out there, so that others know to join in. It's what Anonymous does best.