Since LW is so reticent I shall answer your post.
White House landing has the basics...snickers bars to liptons. Expect to pay premium price (ie more than you expect) on everything. Getting food there means carrying less through the 100 mile wilderness.
If you go there, don't foget the famous 1 pound hamburgers and cheeseburgers. You could also spend night. Everything costs extra.
Boat pick up only at certain times.
They will take credit cards..for a surcharge.
David (snickers class of 06)
PS I presume you know there is also re-supply available at Abol Bridge!