I wouldn't need to know the btc address who sent the payment to the account. You could always blockchain it and see where it came from, but I am only concerned about their bitcoin address on my website. No single user would have the same address, obviously

I was trying to see if there was a sort of smoother way in doing this, rather than allotting a bunch of bitcoin addresses in my database. Maybe whenever somebody clicks create new account it would have their bitcoin address right at the top of the form (that would change everytime the create new account button is hit, until they submit the form)

Just doing some brainstorming for this part of my website, considering this is one of, if not the main part of the website.