Undermining pawn chains at the "wrong" end Usually if there is a blocked pawn chain one is trying to attack it close to its base with a pawn from the side.

For instance, in the classical king's Indian black is playing f5 (not c6) and later (if white plays f3) perhaps even g4 etc. White on the other hand is pushing c5 (not f4).

I am aware why attacking chains in this way is generally the best choice. 

Are there any examples in openings or famous games (besides the French defence f7-f6) where the pawn chain is attacked at the other, "wrong" end?
The first example that springs to mind are the Benoni structures:

[FEN ""]

1. d4 Nf6 2. c4 c5 3. d5 (3. dxc5? e6 {Black recovers the pawn favourably, so we see that 2...c5 induces the d-pawn forwards to be challenged later.}) e6 {Black challenges the head of the pawn chain, rather than the base.} (3... b5 {Attacking the base of the pawn chain with the Benko gambit is also a popular try.})