For me, when I get books I often get the cheaper paperback option, give it a read.
Then if I really liked this book, I'll donate it to a charity shop or in my social circle and purchase the hardcover version.
The only gripe I have with hardcover though is some books come with that sleeve cover around it, you know the one, bit fidgety to use when reading.
Paperback I like if there's a book I am mildly interested in and I'll just go "whatever" I'll keep it as part a collection.
Paperbacks = cheap as chips but aren't as protected as hardcover, easy to fill up your collection or shelf with, might sell it if i want the luxurious version of that book. this is for me.
Hardcover = More luxurious as it provides proper protection to the pages and outer area of the book, Often comes with items as part of a collectors set. Usually I get the same book if I really enjoy it to add as a gem of my shelf.
What are your tastes? Same as me or do you lean more heavily to one or the other?
I think you and I would be good friends. Other than buying books by the Grandmasters, I pick based on the ridiculous cover art. Woman in a space-bikini with an atomic raygun threatened by a lizard/wookie hybrid with a jetpack? Yes please!
Clarke, Niven, and Heinlein for me. The original _Rendezvous with Rama _inspires awe in me every time. Stranger in a Strange Land is beautiful. The Known Space (Ring world) books are among my favorites. I'm also very fond of Ian Bank's The Culture , though they are from this millennium and maybe out of scope for this conversation!
I have and love Burroughs' John Carter of Mars, Zelazny's Amber, and Castle Perilous by John De Chancie. I've just started collecting E. E. "Doc" Smith. I'm slowly adding to my Ursula Leguin and Lester Del Ray shelves.
And I really can't resist buying old yellow books with ridiculous titles like "_Mutiny in Space" , "assault on the gods" , or "The shattered stars". _ Bonus Points for awesome spaceships on the cover. I'll buy those any day without any idea of the author or story.