Perhaps the reason for this stems from the days of clandestine growing where the seed viability and age was almost always unknown.
Otherwise this whole process seems like a elementary school science project. Many of us might recall germinating bean seeds this way in Kindergarten, but not all teachers instructed like so as I recall direct sowing also into our recycled milk containers.
Even with the hardest of shell observed in the modern bred types I am more prone to just cracking or scuffing the seeds as needed.
My only other thought about this being so popular is the fact that many people who sow directly have learned the hard way in regards to what damping off means. Its very easy to find yourself in this situation with unsterile potting soils and other mixes. I think a lot of people have become dependent upon this procedure and it works, so they don’t want to try to fix something that works in the first place.
I do think that if you are going to soak, that you should direct sow afterwards, this is actually common among common gardeners, but they don’t use paper towels and all that in general as they soak just to hydrate and speed up the germination. To each their own though, even though I prefer the better growth and resiliency I see in direct sowing in comparison with tired seedlings that spent a lot of unnecessary energy growing out the tap searching the void.