The PS3 and Xbox 360 versions don't look as good as the PC version on good settings to start with, and then there's mods. With mods, the PC version looks a lot better than even the remastered version. There's no way PC players would eagerly pay for the remastered version, so even trying to make it cost something would be futile and generate tons of badwill. It simply doesn't make any sense for Bethesda to have PC players pay for it. Console gamers, on the other hand, have proven that they don't mind buying remastered versions of games they already own, so from Bethesda's point of view, this all makes a lot of sense. Sorry, but it seems you're in the minority among console gamers here when you're complaining about this.
tl;dr: It's not enough of an upgrade for PC gamers so it wouldn't sell well, but console gamers are willing to pay for remasters even if they're not huge upgrades.
The price is pretty horrible though, but what can you do. A lot of remasters seem to be priced in a pretty hostile manner, yet people buy them anyway. This is a part of the choice you make when you decide you want to play games on consoles. You save on the initial cost (i.e. cost of the hardware) but end up paying more, or in cases like this even a lot more, for software (i.e. games). It's unfortunate, but you can't get both.