Nope, I tested that (yeah, I really did), it's always the same group of chests on the 24 ppl servers.
I have noticed this and am glad there is a thread about it (I would post in the bug tracker section, but I hate having to setup extra accounts for that).
The random chances for chests to be empty are fine, IMHO. The pink house chests do have stuff in them most of the time.
Since no one is being specific about which chests are not filling (and thus not helping the devs fix the problem) here is a short list of chests that don't EVER get filled. Do note that these are chests are ones that I have tested on the servers, as they were part of my route at one time or another. They were empty when I was first to them and again after refill. I also only included ones that were this way for at LEAST 3 games where I am certain I was the first one to the chests after spawn and after refill. So, this list can be taken with some confidence.
Chest 1) Clock tower on map 2 - midway up the tower behind the leaves inside the staircase
Chest 2) Clock tower on map 2 - top of the staircase
Chest 3) Against the glass on map 2 near the vault/capitol building/bank (NE corner of the map) - between the two bluffs against the east glass walls, set into the ground
Chest 4) Nearby chest 3 on map 2 - a bit to the south of chest 3, set into the ground near a tree in the forest
Anyone have any others that are consistently and fairly confidently ALWAYS empty?