There's nothing stopping them, you, me or anyone else here from trading right here in the forums, or on a Google Sheets shared-access spreadsheet, or wherever else. If an exchange is a problem, you can always thread one yourself with 10 or 20 interested others. For example, we've done it with UNO in 2014 with 30-ish users and it worked perfectly, at a small scale.

Obvs, this is for the exchange of bulk packets of coins and clearly is not for day trading type transactions, but the point is, no coin needs to be limited by whichever exchanges support it (notwithstanding the obvious factor of market depth and trading volume being necessary for any coin's longterm health). If there are a lot of people you know who want to buy IOTA, surely some sellers could be found even by offering x BTC for y mIOTA right here in the forums.

Just a thought