The fundamental purpose stated in the bitcoin whitepaper is to provide an electronic equivalent to physical cash.
The first line of the whitepaper[0] is "A purely peer-to-peer version of electronic cash would allow online payments to be sent directly from one party to another"
In practice some "third" party (bank, paypal, square, venmo, etc) will still be involved in most transactions because of the scenarios you have described. But this would be because they are helpful and add value not because they are necessary.
The first line of the whitepaper[0] is "A purely peer-to-peer version of electronic cash would allow online payments to be sent directly from one party to another"
In practice some "third" party (bank, paypal, square, venmo, etc) will still be involved in most transactions because of the scenarios you have described. But this would be because they are helpful and add value not because they are necessary.
[0] https://bitcoin.org/bitcoin.pdf