Bank of the West in Coralville, IA

Went in to this bank a few days ago to get change for a 20$ bill... I understand some banks won't do that if u don't bank with them. But the teller said yes to me then alwardly looked at the bill with uncertainty and said "ahh we can't actually help u out since you don't bank with us" which totally threw me off cause second L's ago he was willing to. Then what seems to be the boss approached me and examined the bill and told the teller if u feel comfortable go a head and exchange the bill. A proceeded to tell me about people being in fake 20's these days. ( isnt that what your special pen is for???) to see if the bill is real or not. The whole situation was awkward and left me never wanting to come back. The disappointing part is that I've been looking to bank with another bank and that bank was on my list. But is now off.