[HarHarVeryFunny]

There's a nice video here of a complete BASIC boot sequence - entering boot code, loading BASIC, then loading a BASIC program.

https://www.youtube.com/watch?v=qv5b1Xowxdk

As far as any program was concerned the TTY was just a serial port, and it couldn't tell the whether data coming in was from keyboard or paper tape reader.

[systems_glitch]

Yup, that's why they were such useful devices! Even if you were ending up with inefficient storage (punching ASCII vs. binary, or expanded BASIC source vs. tokens), it was built-in.