Do codeshare & alliances conflict with competition? I am aware of the advantages that codesharing has on airlines such as 
- allowing airline to expand operations without physically flying to that destination 


creating perception of large flight network
reduced operation costs from seat transfers e.g KLM &amp; Kenya Airways on the NBO-AMS route


However my concern is ;


are there any other further benefits ?
do codeshares reduce competition?
can codesharing airlines compete ? (e.g Star Alliance members, Lufthansa &amp; Thai Airways)
do alliances reduce competition ?
can airlines of the same alliance compete ? (e.g Oneworld members, British Airways &amp; American Airlines)
Alliances are the airline industry's way of corporate mergers. Since national airlines are still regarded as a symbol of national pride and often are part-owned by the respective governments, eradicating the proud name from the industry would be too hard to swallow. Therefore, alliances are formed in which tariffs and schedules are harmonized. The effect for you, the customer, is the effective removal of competition, resulting in monopoly pricing on routes which are served exclusively by carriers of the same alliance.

This can be compared to the car industry: Chevrolet is not competing with Pontiac or Cadillac, regardless of what the advertisements say. You might think that the wider choice of brands is a benefit, but in the end the benefits are mainly on the side of the industry.