Yes. it makes absolute sense that if you put a heavy weight in the middle of a spoked wheel, and one which is then delivering force to that wheel, you're gonna put more strain on those spokes. That's just physics. I'm sure that manifests itself in all sorts of ways, from loosening to breaking and everything in between.
For what it's worth, mine tended to physically go 'pop' when two things came together - weight, due to carrying panniers with latpops etc between offices, and bumpy London roads - either speed bumps or potholes. The pop was invariably the spoke breaking.