To me titleist have simply looked at the big picture:
Golf pro: a loyal stockist who buys in and promotes the gear.
AG: box shifters
I doubt vary much they've done it on such moral grounds.
Most likely they've just realised that long term it will hurt them profits to lose a large revenue stream in pros. Not for clubs, but balls. I'd imagine the mark up on a pack of pro v 1 and the multiple sales at clubs probably accountd for more profit than the odd set of clubs a pro sells.