Karen Is In Control?

Several months ago I got a notice from a legal firm in Florida that my parents had left some some unclaimed funds while retired there.
I'm always suspicious of stuff like this, but I called to see if it was legit. The respondent indicated that all I had to do was fill out some forms they'd send, and the unclaimed money would be mine.
So I punted the project to my son to pursue. And he did.

Four months have passed. Yesterday I got a check. The check is for four figures... not an insignificant sum.
From my checking account I wrote a check to my son for the indicated amount, then endorsed and tried to deposit the (Florida) check to my checking account at our local bank.
"What's this money for?", asks the bank person.
Thinking to myself, "That's none of your damn business!" I lied...
"It's an annuity payment."
I watch as she plinks around on her keyboard. Soon, a puzzled look comes across her face.
She calls her superior to her work station. The superior also gets a puzzled look on her face, then asks, "Is this an annual installment, or a monthly one?"
Now alarm bells go off in my head. I'm trying to make a deposit. The bank will make money on this deposit. They can put a hold on the funds I'm depositing. There is three times the amount of money I'm depositing already in the account. Where is their risk exposure?
I've now reached my tolerance for "Karen".
I say, "If there's a problem with the check, give it back to me and I'll take it to another facility and they'll take it without a problem."
"There's no problem with the check. This is just our rules."
"Then the rule is stupid. I understand you have no control over this stupidity, but I'm VERY close to closing this account and taking my money somewhere else. Take the deposit, or give me back my check. And tell your leadership that they are stupid."

At this point she clicks the keyboard in front her her, prints out the deposit slip; puts the slip into the tray and slides it out to me.

What the hell is going on? The only explanation I can imagine is that this is further information gathering.
Control.

And I like it not at all.