Well the thing to note here is that "grift" is a count noun. (Their definitions as verbs is not what's relevant here!) You can't say "grift is occurring here"; you can say "a grift is occuring here". Meanwhile, "graft", in the sense of the abuse of an office for personal gain, is a mass noun. Perhaps the commenter's mistake was leaving out an article rather than using the wrong word? The latter seems more likely to me, however.
The term you're looking for here is "mass noun" or "uncountable noun", and... well I was going to say "no, it can't", but searching does turn up some uses, so, uh, I guess people are saying that now and I was wrong? It must be pretty new; I'm not seeing it in dictionaries.
(Note that just because "crime" can be used as both a count noun and a mass noun doesn't mean "grift" can be! Most nouns are just one or the other, not both. Like Wiktionary has "crime" as both but "grift" as count only. But it seems like this new uncountable sense of "grift" is out there now, so people will have to update the dictionaries...)
