Can two weak coherent EM beams arriving from different positions cancel out at a meeting point? If two weak EM beams consist of waves with an irregular distribution of light quanta does it mean that if that photons are not uniformly distributed in a wave regarding the time when they arrive and hit the meeting point that in that case they can't cancel out? If this is very hard to understand then I will ask this way: if single photons of two different beams don't arrive at the same moment at a beams meeting point how they should cancel out?
 A: I’ll start with the end of your questions.

If single photons of two different beams (don't) arrive at the same moment at a beams meeting point how they should cancel out?

They will not cancel each other out. Because, where will the energy content go? The observation of the collision of two single photons is infinitesimal. For a beam, even if there were a rare deflection of the colliding photons, the observation shows only the undisturbed beams. However, it would be a nice experiment to prove or disprove the number of incidents.

if ... photons are not uniformly distributed in a wave regarding the time

Photons are never evenly distributed. Simply because there is no such source. And - in addition - only in very limited cases you get an EM wave worthy of the name.
A thermal source, be it a light bulb or even you, emits (and receives) zillions of photons at any given time. The photons come from excited electrons. Even if photons are excited and relaxing at the same time, their position relative to the meeting point is different. And the number of excited/relaxing photons varies over time.
To obtain (and measure) a wave, you have only one option. An alternating current source and an antenna rod. By accelerating the skin electrons in the rod, all in the same direction, the electrons periodically emit polarized photons. You can measure this changing intensity, and this is how a radio receiver works.
Even for such an EM wave it is impossible to neutralize the wave. Otherwise - instead of stealth technology, which attenuates the incoming concerted photons - the enemy radar could be neutralized by its own radar.
