Strip material used in packaging machines is fed by a rotary support unit carrying a roll of a first or a second strip material, installed downstream of a feed unit supplying a first wrapping material along a first direction toward an operating station where inner wrappers are fashioned for the particular packet in production. The first strip material is decoiled by rollers and guided along the first direction to an operating station where coupons are prepared for inclusion as inserts, placed between the inner and outer wrappers of each packet. The second strip material is taken up and diverted by further rollers along a second direction, such that it is supplied to a cellophaner where it is cut and folded to fashion leaflets applied as onserts to the outer wrapper of each packet before being overwrapped.