In the 1970s and 1980s, DC comics had mob ties in a big way. Then in the 90's Marvel comics had shareholders which some of them were connected to the mob. DC knew them, but also knew they could get a loan (which was done legally) without raising too many eyebrows. I know the Tampa family had a local owned small Cigar magazine, and San Francisco family also had a small Wine magazine for the Napa Valley. So yes they did distribute other magazine besides porn. Porn and comics are big money makers and still are for the mob. For comic books most of them are Independent Distributors. I know that the Yakuza makes a killing at Comiket in Japan. The New York Mafia families (now just the Genovese and Lucchese families) had their fingers in The Big Apple Comic Con, and Chicago family started to gain influence in the Chicago Comic con during the 1980's.