Speaking solely for myself as a lapsed D&D player turned Pathfinder player...
I sort of think part of it is a matter of faith - let me explain.
I didn't really care for 4e (but I hasten to add that I know that people do enjoy it and they are fully intelligent, rational people who are not under the sway of the Egg Council) and so after some testing, we play Pathfinder because for us, it was more enjoyable.
And y'know, that's just a matter of game-rule preference, the same reason why I prefer ICONS to Mutants and Masterminds, even though they were created by the same guy.
But here's the thing, Wizards of the Coast lost me as a customer utterly with the approach they took during the 4e transition (which have been long documented elsewhere), so I basically lost faith in Wizards as a company.
So they announced this playtest and from the indications given by the interviews, buzz from early playtests, announcement of the open playtest, my impression was that Wizards was changing - becoming focused on the game and casting off the distractions (such as the 4e transitional advertising campaign), in short it was a smarter, more competent, more mature company.
But then you get to to the OPTL and you see the inanity of it. Sure, game designers aren't lawyers and vice-versa, but this is an ominous sign (to me) because it harkens back to the bad old days of T$R or more recently, the GSL in 4e. In other words, lawyers running the asylum.
And to make a long story short, that makes me wonder if I should bother. After all, I'm already happy to throw my money at Wizards' competition. I won't go through the 4e thing again.
So [MENTION=22779]Hussar[/MENTION], you are absolutely correct that people aren't being forced to do anything and excepting online players, this should have a minimal impact. But human nature being what it is, seeing a company possibly poised to go down the road already travelled is annoying to some who see the pattern clouds start to form.