It works everywhere, but is highly dependent on how full the hotel is, the savvyness of the front desk clerk, the amount you choose to offer, and how realistic your expectations are.
Sometimes you get a clerk willing to do it, other times you won't.
Sometimes the hotel is packed and nothing is available, other times its not.
Sometimes the clerk will do it for $20, other times they'll want more.
If getting the suite is really important, suck it up and pay for it. Otherwise, it is Vegas after all: you have to be willing to take a chance...