On one hand, I am sick and tried of seeing this in half the games being released. It does not mean “role-playing,” it means leveling and/or unlocking abilities. I am still unhappy about the usurpation of the term, and I get tired of grinding in games. The big fight at the end was either balanced assuming a certain amount of leveling, in which case the grind is required, or the levels really are a bonus, in which case the big fight will be trivialized. Neither is good for your game.
On the other hand, I do like customizing characters. It seems that the standard way of doing that is via leveling up and unlocking abilities along the way. This is a good way of introducing options gradually, to give time to learn them, but I would also like a “just give me all the options” button so I can decide how to approach the learning curve. I love being able to pick out how my character looks, how he specializes abilities, what equipment to use, etc. I will put in extra hours to unlock options I will never use, just because I like having more options.
On one foot, that is what it comes down to: we react to the ability to “earn” things whether or not we say we like it. People rate games higher when they have achievements, and we completionists must click off every last thing. If players will lock themselves in Skinner boxes, it is not shocking that developers will offer them.
On the other foot, the other alternative seems to be packing the game with even less optional crap. We decided at some point that games needed to have X hours of gameplay, and you extend your content across X by whatever means necessary. We could have taken the other path, making low-/no-padding games like Portal, but go try to sell a 5-hour video game. This is why we cannot have nice things. Freaking flash games add padding to extend their playtime.
On an unspecified fifth limb, even if I fall prey to your padding, I will still hate you for it. Yes, I am a badge/achievement whore like no other, and I gotta catch ‘em all. (So it’s a good thing I do not play Pokémon, Digimon, Yu-Gi-Oh…) I don’t know how much that will help your bottom line: you are not getting more money from me on a single-player game; in a single-player game I also likely have the option to edit the grind away; in an MMO, I am unhealthily hardcore and am more likely to push a month or two really hard rather than spread the grind over many subscription months; and at any rate, if most of my time was spent grinding, that is the impression I am likely to write about. Not that you are making games for bloggers, but is a buzz of “it pads its content with a ridiculous grind” better than “it is short”?