TVs on the Street

Ok, so I know in some large cities you can look up on certain streets and see large TV screens (I'm thinking about NYC) but why do we not have TVs set up the way that newspaper stands/dispensers are set up around town (you know, all clumped together facing in all directions on the street)? People could walk by and see the headlines (no sound of course). Seems that there could be a lot of money to be made in advertising.