The only place I think altcoins has a future in is gambling, normal gambling but first and foremost e-betting.I can not see how it will take over from normal currency's in the world of buying or selling any other goods then btc. The main reason I think this is that nobody wants to be that guy that bought two pizzas for 10000 btc 5 years from now, so i cant really see what else it has a real future in. But that is only my opinion, What do you guys think?
Though most of the altcoins are that good as we think of but there are still some who are worthy to place our investment. Just like what OP have mentioned it can be used in online gambling but in my opinion it is better for trade. Alts have small transactional fees compared to Bitcoin so I think it will he much better for scalp trading.