Whenever big corporations merge, it is very rarely to the advantage of any entity besides the corporation itself and especially its executive officers. So when airlines merge these days, mostly we as passengers are getting less service for more money and fees we have to spend. All we might get out of it are more routes.
When the airlines merge here in the United States of America most Americans do not benefit from this at all. It takes away the competion at the airports and prices of tickets are more than likely to go up in price. The prices go up because there is less competion.
Air travel has become a nightmare. When airlines merge, the public does not benefit. Fewer airlines mean fewer travel and price options for consumers. Sometimes the mergers happen with little change - for example, Southwest acquired Airtran. I was on a Southwest flight which was canceled and SWA couldn't get me on another flight for 3 days, so I asked about Airtran, and they originally refused to let me on an Airtran flight and refuse to give me the price difference. I didn't benefit from this merger, and most of the time, neither does the general public.
I do not believe many people benefit from airline mergers. Yes, there are some, but far more people are harmed when businesses get larger. I think mergers should be seen as bad for many reasons, but mainly because they eliminate jobs and generally cause prices to climb due to a lack of competition.