That's bupkis, IMO.
While a certain segment of the fan base may think "it's the players job" to sign autographs, it's not really. Their job is the time they spend on the field, court or rink. Anything else they do is discretionary, unless the employer requires it.
The sense of fan entitlement to their time is what many players object to when they come off as "less than enthused" about a request to sign something, pose for a picture or chat like an old friend when it's not in a team-sanctioned setting. Or in a world where it's not atypical for '...I'm a big fan of yours' to make money off their 'memorabilia'...
That so many players are gracious and friendly is actually remarkable. That some aren't, not so much...