Right now, most if not all major banks have mortgage refinance rates about 1% higher than the rate for a mortgage used to purchase a property. Up until a few months ago, I don't recall ever seeing any spread between advertised refinance and purchase rates, never mind such a big one. Is there historical precedent for this practice?
What is stopping a lender from undercutting other banks by offering only an 0.5% spread? Is it collusion that nobody is doing so?