The ShenaniganZ restaurant was actually a converted Bennigan's restaurant (hence the extreme similarities). It has since been completely renovated and is now a Verizon Wireless retail store. (2009)
The "foreign" guests at the bar speak German with Austrian accent and the guy says, "Did you see the blonde girl? That's unbelievable, her breasts are incredible!"
Dane Cook improvised all his character dialogue and name. There was no script given his total screen time of about three minutes, a cameo basically.
The writer & director of Waiting(2005) worked in a real chain restaurant near downtown Orlando FL for 3 years prior to writing the script. The area was near Fashion Square Mall & had a few well known casual dining brands; Red Lobster, Olive Garden, Pizza Hut, Panda Express, Dennys. The restaurant closed in the 2000s & was vacant for many years.
In an original incarnation of the script Calvin was the character who couldn't piss, and Brian was a character who couldn't get the girl. The parts were combined at the last minute.