Why would it be suspicious for an airline to use a system designed to check the flight status of an individual?
Sure, it could be suspicious for an airline to make requests that didn't line up with likely prospective passengers, but that isn't at all how you phrased your second point.
On the second point it's not the airline that it suspicious but the individual on the list. Their actions might be under investigation, and that might include attempting to buy an airplane ticket. What happens if they never actually tried to buy the ticket, but someone was trying to recreate the list? Wouldn't this type of event occur many many times, and the airline might begin to standout.
Sure, it could be suspicious for an airline to make requests that didn't line up with likely prospective passengers, but that isn't at all how you phrased your second point.