just put 4 or 5 in the bowl, and still leave it unaccompanied, but have a sign nearby that says "for larger groups or if the bowl is empty, yell "nigga treat" while ringing the doorbell". the kids who say nigger get full size bars. have a surveillance camera (preferably cctv, not that ring shit), so that if anyone comes back later with some bad intentions after getting pissed at the sign, it'll make it easier for you to get the justice ball rolling.  now that i think about it, for even more plausible deniability, you could have a prop scarecrow or a skeleton with the nametag "nick" on, sitting in a chair holding the bowl, and the sign could say "nick or treat" too.
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