As someone who has worked at Blockbuster in the past, trust me when i say that a grown man renting High School Musical will not even be in the top 10 creepiest thing to go on in the place over the course of a day.
Go on...
I, for one, would like to hear the rest of this list.
Oh man, let's see. There's...
The lady who waits outside for the store to open, and is there before the staff is, to rent her favorite Richard Gere movie for the 150th time.
The man/woman who curses you out in front of their kids because they were charged a late fee on a movie that was almost a month late.
The old guy who rents 2 musicals and a softcore porn video.
The reverse of the above guy.
The woman who asks if Grand Theft Auto is appropriate for her 7-year old.
The guy who takes almost sexual joy in shoving a newspaper ad in front of your face to prove that walmart has the latest release for $.50 cheaper, making you honor the price because there is some fine print on the counter that says we will.
The old woman who tried to return VHS tapes she purchased in 1989 without a receipt. (The manager says to just do it to keep from having to do the paperwork when she bitches to corporate)
The old dude who asks for help from your female coworker in selecting his softcore porn.
...and so on and so on. There are more, but those are all based on actual experience.