I'm much like you. Unless I cash out and convert to fiat which I can use to pay the bills I don't really think about the value of the SBDs. And I certainly don't have any problem giving out upvotes when I like something. It's not like the money comes out of my own wallet (well I suppose it does ultimately if I'm also posting, but I'm not going down that rabbit hole.) In some ways Steemit resembles a game, with SBDs being the points, and SP granting power-ups that make the gaming experience more fun.