While other such adjectives are abused nearly as often, I will focus on these because even a few atheists and scientists abuse these three. An "ism" has nothing inherently to do with belief or worship, nor does it inherently have anything to do with obsession.
An ism is really just an adjective made out of a verb or noun, and that's it. Adding the suffix ism to something makes it "about this," in other words, a single descriptive trait. Thus, materialism is NOT "worshipping of material objects," it means "pertaining to the material world" or the physical world as opposed to the philosophical or imaginary world.
When a person is materialistic it means they are concerned with the physical world, such as food, shelter, safety, … on and on. It does not mean they worship luxury objects, theists often misconstrue this to distract people from the fact that they are greedy and often addicted to luxury objects more than anyone else.
Which brings us to the related, though also misused, adjective of commercialism. Commercialism applies to any system in whicb an arbitrary value is placed on something, even barter and trade is commercialism.
Money is just a marker of value, a scale used to measure the comparative values of everything, even your very life. You earn value by working for it, then you spend that value on things you need and want.
Corporatism is rarely abused as a word, but often people will mistakenly use commercialism when they intend to say corporatism. Corporatism is the incorporation of values, allowing a few elite to decide the worth or value of everything instead of society.
Enter capitalism, another commonly misused word. Capitalism is where the values are determined by society by popularity, what people are able and willing to give for something is it's value and nothing else impacts it.
Back to the original three before I stray too far. Everyone who wants to survive is materialistic, because surviving in the physical world requires that one be concerned with the physical world.
Everyone who adheres to a value system of any sort is a commercalist, if you place a value on your work you are a commercialist. If you believe a god exists then you are a theist, if you don't believe a god exists then you are technically an atheist.
Some isms do include belief, but belief is not inherent. So pull your heads out of your asses and learn to communicate, instead of making everything up like you do in church.