I have no problem if someone tall wants to secure a spot. I don't go early and I don't go in front. I merely want to get a glimpse of the artist and I will take care of myself in order to see, or not. My only complaint is when it's obvious that if someone can't see, and another person (tall in this scenario) is clearly making sure others cannot. Ala Seinfeld, spare a square inch, ya know?
(or, when it's obvious that a person is just that tall, they could see from any spot, maybe they can deal;))
Sorry, for the hijack, but my comparison could be the same for someone w/ a wide girth and/or stance.
One show stands out to me: Travis at the club a few years ago - this guy wouldn't let another guy, who was physically challenged, through the crowded section of the upstairs bar. He kept trying to go around him, but the rude guy was shifting in front of him on purpose. Grrr...still gets my goat.