By Young's double slit experiment it was clearly proved that light was not a rectilinear beam of photons an assumption made by Issac Newton. BUT we still consider light to be a straight beam and we always call them light rays what's wrong in calling them light waves?
I know that it is known light has dual nature but still it is obvious that it has wave like nature.
The point is that even though everything has a wave(function) nature, the form of this wave depends on its physical situation. The wave form of a laser pulse is very peaked around a beam whereas in your situation is quite wide. This wave form only represents the probability of finding an individual (point) photon at some place though. However because of the huge amount of photons you have in your typical light source is, to very good approximation, treated just like a "normal" wave.
