To answer your last question, when the crowds were big, security did routinely escort people out of the fronton for yelling at the players. Of course, you could get away with a few barbs here and there, but security did a pretty good job of walking up to people and telling them to stop their comments and in many cases, if the commentary did not cease, they were escorted. Of course as the crowds started to thin, you could hear the comments more clearly because they weren't drowned out as much by crowd noise, and management was less likely to want to lose even one betting patron, so the fans were able to get away with more. I won't defend it, and it's not right, but it's just the same as in other professional sports where players get booed or are subjected to barbs from the crowd. I think professional athletes have to have a thick skin.
