I am even fine with people 'demoing' a game to see if they want to purchase it (remember demo disks Sony/MS/Nintendo?) as long as people pay for what they play (ie more than a hour), if possible as some games devs or new disks/cartridges don't exist anymore so there is no one to pay. Own or be willing to buy games you find yourself playing that you download if that's the route you go. Backing up your roms/ISOs/CDIs/BINs etc to your PC then playing them via emulation when your old hardware (PC or console) dies and is discontinued should be completely legal/acceptable. You can't buy new old consoles/arcade cabinets or many of the games so this expectation by companies, like Nintendo, that gamers give up their old legally purchased games is ludicrous (or for those who get interested in retro gaming for those who are younger and want to buy/play old games).
