It's illegal to advertise tobacco on television, and hard liquor is never advertised either out of social norms. Also, open and legal production of cannabis would improve quality and variety while open and legal distribution would help too.
Whenever I go grocery shopping, there are the mass-produced cheap beers, but there are also good imports and microbrews. The wine aisle has even greater variety. Why would weed be different?
These are all off-the-top of my head examples of commercials I've seen on TV... maybe you meant broadcast vs cable television? Or are you outside of the US? (I assumed you were in the USA b/c of the no cigarette commercials comment... I think that's only in the US...)
Whenever I go grocery shopping, there are the mass-produced cheap beers, but there are also good imports and microbrews. The wine aisle has even greater variety. Why would weed be different?