I believe this happens a fair amount in the private sector, with some contractors you work with. If you've been doing a job for them and your prices are very similar, for a matter of 5ยข you're not going to go to the low bid. That practice is very good if you're qualified and you're open to do it. But if you've been doing that work for a long time for a certain customer, I think there should be nothing wrong with taking that customer and staying with that work.
On June 6th, 2013. See this statement in context.