As your business matures, it isn't unusual to start becoming more picky about who you want to work for.
I think you're a little young to be taking a major cut to working for annoying people, but surely a price increase will weed out people who wait too long for cleaning because it just isn't a priority to them.
A very successful commercial carpet cleaner who I know has these rules regarding commercial work that he's asked to provide a proposal for:
1. Sign. If there isn't a company sign on the building, they don't have strong commitment to staying there, or being a part of the community.
2. Parking Lot: If it isn't paved, he won't pull in.
3. Landscaping: If they don't care enough about the exterior to invest in landscaping, they likely won't care enough about the carpet and floors to pay for a good cleaning job.
4. Carpet and Floor Condition: He won't give an estimate if the carpet or hard floors are heavily soiled. In his mind, he only wants to work for people who already care enough about their image to keep their floors cleaned, not have them restored each time they are trashed.
Obviously, there are exceptions, but he built a profitable business around that model.