Why is this parallel notebook not maxing out the available memory and processors?

Question

I've searched many questions about parallel processing here, and they are either specialized or over my head. I run the following parallel notebook on an 8 core EC2 instance. The average memory usage is ~40% of 32GB and the CPU utilization is ~50%. Using "CoarsestGrained" does not help. Why is it not maxing out the system capacity?

Remove["Global`*"];
LaunchKernels[];
mccount = 10^6;
cyclesperday = RandomVariate[LogNormalDistribution[-0.9, 1.3], 635554];
samplemanycyclesper5years = 
  ParallelTable[
   Total[RandomChoice[cyclesperday, 1826]], {100*mccount}];
cycledatatofit = Partition[samplemanycyclesper5years, 100];
samplecycledistributions = 
  ParallelTable[
   EstimatedDistribution[cycledatatofit[[i]], 
    LogNormalDistribution[\[Mu], \[Sigma]]], {i, 1, mccount}];
samplecycledistributions[[1]]