What? This is a case where two people did something unusual in a work environment and garnered the attention of their coworkers. That's expected. It's unexpected that you think it necessarily implies sexual objectification.
Go stand in the middle of your office tomorrow and hoola hoop. Whatever sex you are, and whatever sex your coworkers are, I promise you'll get looks for long enough to be considered gawking :) If you choose to complain to HR that you were sexually objectified, well, that's up to you.
I'm not saying it Wasn't sexual objectification, just that to gawk at something unusual in the office doesn't necessarily imply sexual objectification.