I don't see that as a real issue , unless you are trying not to be tracked and are paranoid about privacy.
Consolidating that dust is a nice way to earn a few Satoshi from that attack, as pointed out by loycev.
ONLY do this if the spam dust is sent to the same address, for privacy reasons (combining spam from different addresses suggests the same individual owns them all)
That guy must be really lucky (or unlucky) to get attacked on two addresses on the same wallet. But yeah, it is also worth pointing out not to combine with other addresses which you can be identified (used by exchanges withdrawal/deposits or whatever)