It's not like Spicer's doing this in some private room.

'Fuck your camera ban'. Seriously.

if they turn their cameras on?..

to calm down , these investigations take time. The truth will come out eventually. It took 2 years to take down Nixon. Look around my friends the shit is hitting the fan by the hour. Russian involvement in the elections is far worse than first thought. Healthcare is inches away from real disaster. This story about media(such as it is) being restricted except friendly state sponsored Fox and god knows what else is going on while trump tweets. In a short year the damage done very well may be too much to reverse. Meanwhile it seems nothing will be done to secure elections so waiting for 2018 or 2020 seems like spitting into the wind.

In fact the first move in the autocrat playbook is to delegitimize and co-opt the real media.
That's what's going on here - this is another step towards autocracy/dictatorship.
This president is trying to destroy American democracy.

Money will make the media move. Are they going to do something about this?

Create chaos.