Monero/DASH/insert anon coin may not be as relevant in the "real" world, but it could revolutionize the way money laundering, tax evasion, hiding assets, black markets etc work. So it might have a much smaller userbase, but all of those are potentially trillion dollar markets.
I don't see Monero succeeding if bitcoin fails. But if bitcoin goes mainstream, and people start to readily accept non-government backed online currencies, then I believe it is inevitable that such activities will also move to crypto; and it will be an anon coin rather than bitcoin.
I really don't care about things that are going to revolutionize illegal actions and neither should you. It wouldn't surprise me if something bad happens related to Monero or DASH and the US goes after its creators. We have way too many coins as it is now. If everyone who ever worked on altcoins or contributed to them had done that to Bitcoin only, we would already be living in the age of digital currency.
They're just leeching off of Bitcoin, nothing else.
black listed or not, those coins will find always a use for some people, they are here to stay no matter what happens to bitcoin, because they offer something that for someone is valuable alot and that bitcoin does not serve in a successful way, privacy and anonymity
those coins can become obsolete only if sidechain will promise the same anonimity via zerocoin or darkwallet
Good luck avoiding legal actions against you for using them. Sidechains aren't designed for anonymity, but for transaction scale-ability. They just supposed to exponentially increase the amount of transactions that the network can handle. However, there could be some anonymity involved when exchanging BTC -> Sidechain -> BTC.