I have to disagree on this. Sometimes DL flyers have to drive rather substantial distances — in what may turn out to be rather inclement weather — to get to DL hub and focus city airports and deal with whatever is going on with traffic on the roads to the airports and whatever the situation is at the DL airport/terminal. And an airport-bound roadtrip which takes maybe 1-5 hours on a good day to a DL airport can sometimes take twice that or longer on a bad day and the variance can be extreme enough that it just makes sense to try to get there hours earlier than when the weather and traffic picture is all rosy. And when not able or willing to just ditch the car and get a quick replacement drive mid-journey, it sometimes becomes even more necessary at times to plan on being at the airport even way earlier than 3 or 4 hours before scheduled departure even if the weather and traffic picture looks good. Add on how finicky airlines can be with international check-in at times and their limited capacity for manual check-in, and there are good reasons why passengers entitled to lounge access may want to spend more than 3 hours in the lounges so as to try to get work done.