Say you're working in a call-center for an insurance company. You could look at it one way - you're a small part of a great thing, the idea of inn-sewer-ants, that means people in society have some level of safety when things go wrong.
But it becomes alienating when you see that it, along with pretty much all business, is a construct to funnel wealth to the people at the top, whilst extracting as much value as it can from the powerless people at the bottom.
Capitalism is innately more alienating the closer to the bottom you are, because due to the division of labour, people no longer have much of a connection to the results of the work they are doing, unless they are in an industry that is innately creative, such as coding, or vocational and involves seeing the direct results of helping people out.