That really depends on the context. There's something to be said about a monopoly's buying power, the consumer benefits from that. A Brunswick marine supply distributor which I now use often, used to be one of my last resorts because their pricing was much higher than their competitors. After acquiring another major distributor and amalgamating the two which most thought was going to be a bad thing since the distributor they had just acquired had excellent pricing, much to everyone's surprise, their pricing suddenly became one of the best in the industry here. That benefits me and my customers.
A flip side example is one of a local marina conglomerate that sells a ton of boats but members at just about every one of their marinas have the same complaint; they are more focused on new boat sales than their existing marina members. Their techs are too busy getting new boats ready so member boat repairs get sidelined. This was never the case with the previous marina ownership. I worked for a few OEM dealerships and that goes on all the time. The techs always have to scramble to accommodate the short notice delivery promises sales people make.
There's pros and cons for sure but it's not always a bad thing, sometimes it's for the best.