If the business owner paid immigrants the same living or otherwise higher wage then they would still be taking (or the business would be giving if you prefer) t

If the business owner paid immigrants the same living or otherwise higher wage then they would still be taking (or the business would be giving if you prefer) the jobs from the locals. This would also create an incentive to hire locals because they know the language and culture. However, there is no way for the wage to stay high while the you increase the supply of labour from a handful of locals to the entire poor population of the world. Illegal immigrants are entirely complicit here. They want to make a few bucks just like the business owners want to save a few bucks. This is a classic tragedy of the commons (the commons here being a nice western country). The only party that can fix things is the government. Or an owner of the country if there was one.