Is This Acceptable Behavior By a Bank?

Today is Saturday, and I wanted to make a quick trip to the bank to deposit two checks before the bank closed at 12:30. When I got there, there were two tellers on duty, both of whom had customers. I was first in line for whichever one opened up. The one teller had a family whose transaction apparently included applying for a credit card. The other had a husband and wife who seemed to be applying for something. The family was answering many questions and in general having a long discussion about the credit card application. The couple were also in a long discussion about their application, whatever it was. People began getting in line behind me, but the two tellers seemed in no hurry. At one point, the teller with the couple asked for information that I thought she shouldn't be asking them to repeat in public, such as their annual income, place of employment etc. Certainly anyone in line who was paying attention heard the couple's annual income. It seemed to me that that sort of question should have been asked in private, and, in general, that long transactions should be done by bank officers in their offices when there is a small number of tellers on duty. Finally, after about ten minutes, when there were five people behind me, the couple was done and I was served. The family applying for the credit card wasn't finished until five minutes after I was served. I didn't see either party begin their transaction, but I can say that one transaction took at least 15 minutes and the other one at least 10 minutes.

Am I wrong in thinking that (a) when there is a limited number of tellers, they should refer lengthy applications to the bank officers, and that (b) they shouldn't ask people for personal financial information with a crowd listening? I've never worked in a bank, so I am not positive what standard practices are.