Usually, mass media aims to reach a very large market, such as the entire population of a country. By contrast, local media covers a much smaller population and area, focusing on regional news of interest, while specialty media is provided for particular demographic groups.
The advantage of running operation in mass media is that one can set up a platform of medium to disseminate favorable message.
The advantage of attacking mass media is that one can build up his/her reputation for being less biased and more objective.
The advantage of co-operating with mass media is that one can ease the worries of being "black mouthed" by media organizations.
The advantage of buying corporate engaged in mass media is that one can get a big asset for negotiation with political parties and the government.
Disadvantages of mass media
Well I believe it comes down to the parents or guardians to begin with. Of course younger generations shouldn't be watching as much TV if at all.
Most of the primetime shows and stations are becoming more and more passive on what not to show. Having younger children subjected to nudity, cursing, sexual immorality, drinking and other negative adult oriented material is of course unsuitable, heck even...