the fun part about the alts is ... they're all priced in btc ... so if btc ultimately fails / severely loses value , so does every single alt coin ...
I'm also not fan of altcoins, but to be the devils' advocate: Altcoins could have a better performance (compared to BTC), so it could make sense to invest in them. Also, there
may be an altcoin - at some point in the future - that could prove to be more successful than Bitcoin in general!