This is a difficult question to answer because there were so many different people coming to and living in the West in the nineteenth century - and it was in itself an enormous place with "many Wests" as historians of the period and place like to say. Even the clichéd "Wild West" with a frontier town surrounded by open expanse tended to have more foreign-born and diversity than many Eastern cities. Since tastes varied radically, different saloons would open, often catering to a segment of the population. Because of this, one saloon might sell more whiskey while the one next door might specialize in fine wines, and other with imported and/or domestic beers. Most saloons would sell an assortment of everything, but preferences of clientele is hinted at when one compares the archaeological evidence of different establishments, which shows that they weren't consuming the same proportions of wines, beers, and hard liquor in each place.

On top of this complexity is the fact that you can't trust the facts! Western communities often boasted that theirs was the hardest drinking town around with more saloons than anywhere else and an annual consumption that was unmatched. The only thing that you can count on was that they all tended to boast the same thing, and none of them were in fact the 'Hardest Drinking Town in the West" - they were all contenders! But the boast survived and influenced the popular perception of the Old West, giving it some of its "Wild" veneer.

But then ... there is at least one fact that does affect all of this, namely the demography of the nineteenth-century West. Although there were more women (and most were not prostitutes - another bit of "Wild West" hype) and more children than the cliché, there was in fact a preponderance of young single men, and young single men being who they are, they did drink a lot. One of the first businesses that would set up in a new Western mining town was a saloon, and there were always ample customers.

All this adds up to an answer with equivocations: everyone drinking something (often but not always it was whiskey) is sort of accurate, but it is based on exaggeration, and it doesn't capture the complexity of reality: not everyone drank; there were at least some families where drinking habits were different from those of single men; there was a lot of whiskey, but there were also many other types of drinks; and consumption was not as dramatic as the cliché would have it.

I hope this helps!