Neil:
Until now I hadn't closely followed this thread but I just read it and the question seems to be if there was a connection between architects and seed companies and such. There certainly was and it seems to have gone pretty far back with some particularly the GB architects such as Colt. William Gordon who apparently became the foreman for Toomey and Flynn in 1923 had represented the Petersen Seed company and then became the superintendent of the Carters Tested Seed Co's construction division in 1920. (It should be noted that these major seed companies back then were involved in more than just golf).
What I can contribute to this subject is how the USGA (and the US Dept of Agriculture) looked at this situation and how it apparently to some extent inspired the creation of the USGA Green Section. The ceation of the USGA Green Section is a pretty long and involved evolution that spanned almost twenty years until it became completely formalized somewhat as we now know it. All those years it worked very closely with the US Dept of Agriculture for their grass research work.
Over those early years the major players in the effort were Walter Harban, DC, Macdonald, Hugh and Alan Wilson, Philadelphia, E.J. Marshall, Toledo Ohio from the club side and Piper, Oakley and Carrier from the government side.
It is pretty clear to see that those men above felt that golf generally in agronomy, construction etc had reached (perhaps by the early 1920s) a total national cost of $25,000,000 and that up to a third of that was waste via mistakes made and the poor seed products of what they referred to as fraudulent seed-merchants.
The correspondence that initiated the setting up of the USGA Green Section is literally a few thousand letters and it seems the two most responsible for this effort from the club side were Hugh and Alan Wilson of Philadelphia (Alan was the first USGA Green Committee chairman). The USGA Green Committee was apparently charged with setting up the USGA Green Section. Initially their intention was to raise and endowment fund of $1 million dollars of which the yield would run and fund the Green Section and the government agronomic research. I do not believe that goal was ever reached but to prepare for it a Pennsylvania corporation was created in the early 1920s called The USGA Green Section Endowment Fund, Inc. It was set up to create tax deductibility on contributions.
There is no question at all most all these fellows were imbued with a pretty intense "amateur" ethic about the game and various involvements with it. To say they were originally pretty "anti-commercial" would definitely not be an overstatement.
By the way, perhaps around 1925 there is correspondence between Alan Wilson (representing the USGA) and the US Government (Dept of Agriculture) about the idea of the professional architects setting up their own association or society (the professional architects in America were apparently making noises to that effect) and Alan Wilson's advice was to just let them do it on their own without any involvement from the USGA and certainly not from the US Dept of Agriculture. Their only assistance would be just mentioning it in the USGA Green Section Bulletin, if that, even though Alan Wilson did allow as a professional architects association would probably be good for golf somehow.
Actually, if the likes of the Wilsons, Macdonald, Marshall, Vanderpool et al from the USGA seemed anti-commercial, the men from the US Dept of Agriculture, Piper, Oakley were even more so. Ironically, in the early 1920s their best researcher, Lyman Carrier decided, to go over to the commercial side creating true disappointment. They talked about the need to pay him enough money to get him back to the US Dept of Agriculture/USGA Green Section side but that did not happen.