Ok fine you got me Dammit
I'll play devil's advocate and go along with your argument, although you supported it like a 10 year old.
Exposure can be the linchpin in getting a shot at the league. Look at Kenneth Faried out of Morehead State. You can't convince me that he gets drafted at 21 without the exposure he got in the NCAA Tournament. Without Morehead's inexplicable mini-run (jacked up 99.9% of the world's brackets!), they'd glance at his measurables and scoff at the thought of sticking him at power forward.
Another example is almost any player ever drafted that went to Duke. They're typically smart system players that get airtime others with more NBA-worthy games don't. As a particularly supportive example, Shelden Williams went fifth in the '06 draft. In the same draft Paul Millsap went 47 overall. If these two switched the names on their college jerseys, they'd see comparable switches in their draft positions.
Of course, these are exceptions to the rule. NBA scouts generally do a good job in identifying talent regardless of a kid's pedigree. But you can't say that exposure - or lack thereof - doesn't matter.