Mysteries of the Deposit Slip

Having worked closely with all the major local commercial banks for the past couple of years with Dragonpay, there are some things about the ubiquitous deposit slip that has always boggled me.

Mystery #1 - Account Type

Why do banks ask us to tick the box if the type of account we are depositing to is a "Checking" or "Savings"?  Can't the teller tell (no pun there)?  Surely by simply encoding the account number in their screen, their system can immediately tell if its a Checking or Savings account.  So why even bother asking the depositor to tick it?

I noticed that even if you leave this field blank, the teller will just process it anyway without asking.  This proves that they can easily tell from their screen.  So why bother asking?

Kudos to banks like Metrobank whose deposit slip has never seem to have bothered asking for this data as far as I can recall.  The 4th digit of your bank account number already tells them if its a PHP or USD, Savings or Checking account.  No need to ask.

Mystery #2 - Date

Why on earth do banks ask you to write the date on the deposit slip?  Isn't it obvious?  Its always the date of that day.  The teller will never accept a deposit slip which is dated in the past, nor in the future.  The teller will only accept current dated deposit slips.  So again -- why bother asking?

All banks print validation data on the slip when the teller processes it.  And all validation data contains the date and time it was processed.  So since the date is already there (based on the back-end system), why are they still asking the depositor to write it?

Mystery #3 - Currency

To a lesser extent, this field is similar to the account type field in my opinion.  When the teller types in your account number in their system, they can already tell what is the currency of your account.  So why bother asking you?

Mystery #4 - Signature

Why do several banks ask you to sign on the deposit slip?  Of what value does it serve?  Metrobank, Landbank, UCPB, etc. have this field that perplexes me.  The teller never actually validates if that is really your signature by comparing it against a government-issued ID.  You can ask your 3-year old kid to doodle in that box and it would not make any difference.  Why, oh why?

Mystery #5 - Relationship to the Account Holder

This one seems to be unique to Landbank and UCPB.  You (the depositor) have to declare your relationship to the account holder on the deposit slip.  Why on earth is that important?!