I think it's possible you're both right. There will be cases where you need to drop a client because they're not willing to pay you enough for keeping them to b

I think it's possible you're both right. There will be cases where you need to drop a client because they're not willing to pay you enough for keeping them to be profitable (parent's point). On the other hand, there's a whole "low-end" market available to some people who have the resources to band together a large number of very-low-profit customers into a product that ultimately still makes you money (your point). If you can find such a market, then providing a service to these people is economically justifiable.