Does anyone know of retailers which sell goods/services for crypto only with no option of payment made in fiat?
Could this represent a good business model for a small store with an online only presence?
There must be some holding alts who are fustrated by the lack of options in terms items they can spend their coins on. While there are many options for bitcoin, for the most part alts are neglected and there isn't a huge market where they can be utilized without first having to convert to btc.
Could support for ripple, eth, bcc, doge, ltc, dash and other alts be a good foundation upon which to build a small business?

As of now, I don't think there are retailers or marketers that sell good or services with cryptocurrencies as exclusive means of payment. I think that would not be a wise choice for them because money is still more main stream and is more widely used by people. For now, crypto-payment is only an additional option because even companies that use it are only in their testing or experimentation stages. On the topic if its a good business move to allow cryptos to be used as payment; I would say yes because it gives people more options and it opens revenue to other customers that are not local to where the physical shop is.