If there is a big enough market with Cryptonight coins, then yes. ASICs support the most popular algos. If more coins start being built with that algo and Bitmain can profit from building a Cryptonight ASIC, then we will see them being sold.
This is semi-correct. CryptoNight is setup in a way that is memory intensive. Memory on an ASIC is very expensive, making it extremely expensive to make an ASIC for cryptonight (same goes for ethash).