believe me, Intuit bottom line is not hurting.

The stock is going up up up.

You agreed to pay from your bank account if your refund is reduced to below the fee, denied or delayed.

And you should pay upfront with a credit card to avoid the Extra $40 Refund Processing Service charge (45 in California).  Having the fees deducted from your refund doesn't make you get the refund any faster and may even add a day or 2 since it has to go through the 3rd party bank to take the fees out.

If the IRS is taking too long to send your refund or reduces it see.....
https://ttlc.intuit.com/community/payments/help/what-if-my-federal-refund-isn-t-enough-to-cover-my-t...

Then when the IRS does send your refund they won't take the fees out again.

And, Why you got charged,
https://ttlc.intuit.com/community/charges-and-fees/help/why-was-my-bank-account-auto-debited-for-tur...

You should have received about 4 emails asking for the fees. If you don't pay they will debit your account. You had to agree to it. Check your spam folder for emails.

The generic payment warning  debit emails are just that ... generic.   When you entered the routing & account numbers in the program the processing bank doesn't know what type of account it  is  since checking accts, savings accts, broker's accounts with check writing privilege's and pre paid debit cards  all use the  same routing/account numbers formats so in the TT system they are all the same.  

That said ...  even if your bank said the debit could not happen from a savings account I would not count on it ... although paying bills from a savings account is highly discouraged by virtue of  limits and fees that are imposed  they are not forbidden so your sweeping statement  is not the entire truth for all banks.