When they started doing e-tickets, security at one of my home airports didn't know how to deal with them, with the result that they changed the rule so a ticket/bp was not needed to access the secure area - a rule that persists to this day.

Now ... your e-ticket receipt is supposed to be the equivalent of a ticket for immigration and security purposes; and for international-to-US flights, I think you have to check in outside the secure area and get a bp anyhow.

Curious thing about airport security: I discover that when I travel without my LL Bean hand luggage, I always get a secondary in BOS (and never when I have it); in BWI,
the exact opposite holds. Strikes me that at
one of these airports someone is misapplying the profile?