I wouldn't go quite that far. I've had a couple of very good banks go out of their way to support their business customers, both who worked diligently to convince me to move all my personal and banking business to their bank or offering business loans at very competitive rates. One (PNC Bank) rep would take me to lunch about once a month to see if they could do more business with me, and the branch manager there always went out of her way to help any time I needed it. I was about to move a couple of additional accounts over to them when they abruptly were sold and changed names and staff, and our relationship immediately grew cold. I stayed with them another 6 months or so, then left them when their drive-thru lane became too annoyingly slow, always keeping me waiting far longer than necessary.
Again, never got a call back or an inquiry as to why I took my business elsewhere. I believe many banks could stand to take a few lessons on maintaining a good relationship with their customers.