The landing gear shown during take off are those of a Boeing 747, an aircraft where the cockpit is on the small upper deck. Scenes of the cabin show the cockpit at the front of single deck aircraft.
The distance between LA and Vegas is about 275 miles, which is less than a 30 minute flight for a commercial airliner. There would be no time to do a drink service on the flight. However, many scenes in the series show this.