We were in town for the ConExpo 2014 with our Italian coworkers who wanted to see the Grand Canal at The Venetian and of course have an American burger. After a bit of wandering, we ended up at I Love Burgers in The Palazzo.
The service was so so for it not being too crowded. (It probably didn't help the guys from Italy needed some help with the menu although we successfully introduced them to tater tots and sweet potato fries! Both are very good by the way.)
Also, if you're getting a draft beer, two 16 ouncers is cheaper than one 32 ouncer. Leave it to Vegas to throw economies of scale out the window. I got the Oregon Trail which is a buffalo burger on wheat. Great tasting, but the patty is disappointingly SMALL.