No, "cheap" on the backs of others is never a good practice, in my book.
There are several large retailers that we do not go to because they don't treat their employees well. Some do this through gender-based pay discrimination. Some do this by hiring a majority of part time staff so that they corporations do not have to pay benefits. Others are just flat-out terrible places to work, period.
Which policies are most important to me? Those which uphold human rights and dignity. This means that their employees are treated relatively well and receive reasonable compensation. This means that the corporation isn't practicing gender-based, racially-based or any other sort of discrimination that diminishes/devalues the rights of others. I have boycotted O. large retailer for their support of a candidate who would continue to degrade the rights of gay and lesbian US Citizens. I care where my money goes, and whom it supports. Human rights policies are the most important, and that's pretty broad, I know.
I do think about all these things, too, when buying toys for my son as well as household goods. Which are the most durable/ least disposable? Which are made with good practices for the environment? When we purchase toys, I want them to be of high quality, so I can use them for a long time within my family, within my business, and then pass them on. I also want to be sure that playing with them won't become a health hazard, or contribute to the degradation of the earth or any community of peoples.
We also want to support organic and healthy farming practices, so we buy from certified organic farmers, as well as the grocery stores which would put local farmers first and sell 'conventionally grown' as the last option. Monsanto doesn't need more of my money, these farmers do.
We rent from the local video store, too, instead of relying on Netflix. Our local store is a landmark and a part of the local economy. I think of this every time I see O. of the clerks out at the grocery store or at the pub. Because I go there, because others like me value what they have to offer, these younger people have a job. Ditto local cafes.
I want to do what I can to support a better world. To me, this means being thoughtful about what I'm buying, why I'm purchasing it, if it's needed, etc. I don't need more of anything, really. Most of our non-food purchases are merely to replace things we have worn out or grown out of. (like my son's clothes, esp.) Most of our money is spent on necessities, utilities, food, mortgage. To corporations however, I don't have any 'voice' other than my wallet.