If you buy graded, you can remove it from the plastic and put it into binders. Many of us here do that:
https://www.net54baseball.com/showthread.php?t=200591
Not much anyone can do with your email. Mine is
tiger8mush@yahoo.com and I'm sure I've posted it here 100s of times. I guess you could sign me up for spam but otherwise its like knowing your street address or your license plate.
I do agree though, if someone is posting for sale on the forum, I prefer to see pics. I almost never request a pic if they don't post one. Many times I've made a purchase based on a pic of a card I think looks neat that otherwise I wouldn't have.