Empty/abandoned = fewer normal objects you can/would interact with.

Good versatile reactive AI takes ALOT of programming (remember what a big deal they made about Half-Life when it STILL was just largely scripted events particular to the specific situation - just they had more logic than most previous games did, still fell apart very fast when you did untypical things)

Things (objects) react to other things (not just to the player) so all the cascade of interactions which you would expect if its simulating realisticly suddenly geometrically expands the processing (and overlapping flavors of special effacts).

Much easier to paint some bullet/scorch/blast decals and have standard flames without needing to have NPCs running away on fire screaming (setting other things on fire or dying in unique ways utter curses at you) and all the other reactions/interactions a human might do appropriately.

Everything costs and having alot of stuff which might amuse you to play with (like GTA goes a ways with that - but if you watch you soon realize how repetative it can be) but finally does nothing for the story plot is a waste when they have a limited budget.

Really good AI to make them interact in a sophisticated way takes even more programming and runtime computing capacity (like magnitudes more) which limits you on todays hardware (so the important 'opponents'/story characters you have already get whatever resources they do have)

SO much easier to have an empty area devoid of interactive objects which would if present have to stand around like mannequin dummies and react/non-react to whatever you are allowed to do in a similar boring/illogical way.

art is a reflection of the soul

I think game designer take platform constrains into account of what is feasible. So avoid situations that are not feasible and don't fit into the game.

So a massive online D-day WW2 landing event with 10.000 vs 10.000 not feasible.

A fire fight middle in a 50.000 concert of popband is not feasible.

The predator movie event cutting down jungle with a gatling gun in photorealistic why with high fidelity of jungle leave physics interaction in fine grain detail. not feasible.

So it is not laziness it is often just not feasible.

Rather its first person shooters or zombie games, All types of games are populated with empty or abandoned environments. Is it because it's easier to do? Could be it laziness or lack of creativity?
What is your opinion on the matter?

It would just be easier. As Servant Of The Lord said, video cards render flat objects better. It's also easier because you might not have to make a whole set of characters, such as mobs for that area.

+1 to Ravyne.

It is quite depressing what toaster the average PC gamer is gaming on. The new consoles, which are hardly groundbreaking when it comes to hardware power, look quite advanced in comparison!

The fact that the average worldwide user for western game dev companies has moved "east" so to say, has not helped either. Read somewhere that escpecially in russia, the common game PC is using hardware that is completly obsolete by western standarts.

Still people see the screenshots with all the cool postprocessing and high polygon character models and start to expect that. If you have to have AO, Global Illum, and a highly detailed Player character, something else got to give, right?

Which game dev in his right mind would start to put in huge crowds of people, or huge amount of plants into his game, when he is already close to the limit of what the toaster users can play with 15 FPS even on the lowest graphics settings without it?