Even if it isn't the only game in the world, from the 'other' side, saying it is alright just for the fact 'it is something to do' or 'you can play another game' is a horrible argument. Yeah, a decent argument as a player, but you essentially tell them 'good, we don't need ya, go off to y'r other stinkin' games'. Well, you essentially just told'm to stop investing in SE. I know if that were to happen to my designs I'd at least have a little bit of a bitter aftertaste.
And yeah, both sides have some absolute scum defending/attacking the matter. However, a game, or in an MMO's case, the content should be good enough you're willing to defend it against veteran players by mentioning the content/mechanics/quirkiness it has. Not because 'there is another fish in the sea'. I can't say I've seen such an argument delivered more than three times by the 'defending' side.
Meanwhile the attacking side, while spewing their own vile, has also provoked thought many more times and shown many more arguments in their opinion's favor. And no, I didn't bloat the stats with carbon copies.
Last time I grinded, it a) wasn't as long in either of the genres you depicted unless it was a survival mode and b) it was worth the effort way more. Justifying a massive grind just because there have been grinds is really passé.
