Can't say I think stress would be a problem, but I certainly didn't think of that issue either.
Not really sure how much stress could be there. The hub sits flat on the counter and the end of the MR3040, which doesn't weigh much, is elevated about 2mm. I suppose some folded paper or a couple of popsicle sticks under the end of the 3040 would eliminate any pressure, if that was a concern.
Now, if a large dictionary fell on the MR3040, that would be stress.