Banananananana juggling

So this morning I did my usual wander to walk only to disover that the level crossing is being ripped up and I had to divert my wandering under the subway to carry on. Not a problem, just a bit annoying, but never mind.

Anyway, this is spray painted on one of the walls under there and I thought I'd share this with you and see if any of you can figure out what the meaning is...