For me having a token issued by an exchange is a sign of confidence,stability and maturity. It offers me a new and additional trading pair. Normally exchanges offer trading pairs. These trading pairs are mostly pegged to one of the more prominent crypto currencies like BTC or ETH .
In my trading experience When you are trading a pair say pegged to BTC a large swing in the price of BTC normally adversely affects the price of the othe cryptocurrencies and at such times there is very little place to park your funds.

Source Article