I agree - mostly. I think if a former player wants to not be bothered after retiring (Ricky Wright, Mike Ivie for example), then they have the right to do so. They have contributed to the game of baseball and they have turned the page with their career and life.I'd like to think of it as they should feel a certain debt of gratitude to their fan base.
I believe current and former players have the right to charge whatever they want for their signature. Simple economics will decide whether they will either (a) have a steady revenue stream or (b) have limited or zero revenue from the price they demand.