Given how that album is responsible for 3 out of 5 of their biggest hits, you are being very bold (and not too bright) with this statement. Especially when one of the other two has no chance due to vocal demands of being opted for Jon to play on a high profile televised performance like this one.

There is no rule regarding this. GNR played songs from Appetite only.

Plus, what "it's about" is purely your interpretation.