Nobody forces you to buy the remasters / ports for full price, when they are released... their prices fall fast enough and you can get them if the value is right for you. If you already have played the original game it should be easy enough to wait until that point is reached.
I bought the Tomb Raider Definitive Edition for €11.99 earlier this year (even minus 20% for filling my PSN wallet).
"The Last of Us Remastered" included the new €15-DLC "Left Behind" which I gladly hadn't bought yet for PS3 when the PS4 announcement arrived. So I sold my PS3-version for €25 right after the announcement and bought the PS4-version in the summer for €37... and paid eventually less for the prettier version (plus commentaries, photo mode, 60 fps...) than if I had sticked to my PS3 version + DLC costs.
Thanks to Cross-buy I got the (later released) PS4-versions of Escape Plan, FEZ, flOw, Flower, Hotline Miami, The Unfinished Swan and Thomas Was Alone for free... definitively no cash-grab. I also got the (later released) Vita-versions of Resogun, Entwined, God of War collection, Jak collection, Ratchet collection and Sly collection for free, so I can play them on the go.
Of course I had to buy these collections (God of War, Jak and Daxter, Ratchet & Clank, Sly Trilogy) first... but they were cheaper than the money I got for selling the PS2 versions.
The Halo MCC collection (plus 5€ for ODST) was also cheaper than the money I got from selling the 360-versions of my Halo games.
The upgrade from my GC-version of Wind Waker to the Wii-U-remake was a no-brainer... I got it as a bonus game with my Mario Kart 8 purchase and still got over €40 for my old limited edition (which included the N64 version of Ocarina of Time, but I got its 3DS version for €20)
If I include late ports to PC (Alan Wake, Brutal Legend, Gears of War, GTA IV, Mass Effect, Resident Evil 5...) I can't complain: in most cases I got more for my used 360-version than the price of the prettier PC-version.
The remastered version of "God of War 3" (only 1 game) seems overpriced for me, so I will wait for a price cut. The Uncharted collection (3 games) is better priced, but it depends on my backlog, if if get it this year or wait for a price cut.
