Such mergers can be either a good thing or a bad thing, depending entirely on one's perspective.

On the one hand, essentially getting rid of potential competition, or forming partnerships with complementary product lines, gives these giants even more monopoly power than they already have. Monopoly power can and often does lead to some kind of abuse, usually not against their customers however. Abuse can take many forms such as tax avoidance, unfair treatment of employees, supplier abuse, environmental abuse, etc., etc., etc.

On the other hand, this is usually great for the average consumer. Take Amazon for example: Anyone can buy from Amazon, and if their total purchase is just $25 or more, they can get it delivered for free, and if the customer is not happy with it for any reason, Amazon will take it back, provide a full refund, and even pay for return shipping. Try getting all that with virtually any small company! Almost Never! Rarely can you buy such low value items on line from smaller companies, and have them delivered for free. And if you are not happy, virtually never can you get a full refund (including shipping and handling), let alone have the vendor pay for return shipping.

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