(a) The income from any vending machines which are located within reasonable proximity to and are in direct competition with a vending stand for which a permit has been issued under these regulations shall be assigned to the operator of such stand.

(b) If a vending machine vends articles of a type authorized by the permit and is so located that it attracts customers who would otherwise patronize the vending stand, such machine shall be deemed to be in reasonable proximity to and direct competition with the stand.