Rob
This type of support seems to be acceptable with most people here.
I do not see that, what I see is that most of feel it is not an NEC violation.
This is not a 3/4" run its a feeder with much more weight involved
No matter what that 2" is filled with that plumbers tape will hold it.
Perhaps you are not familiar with it's strength.
Plumbers have used that for years supporting cast iron waste pipes.
Keep in mind that the code is just a minimum, if you feel that needs 3/4" rod you are more than free to do so.
