Everything depends on large investors. If the bounty company is renewed it means that it was not possible to collect the planned amount. It happens that before the time is collected hard cap and bounty the company closes.
I do not think that this attribute is of fraudsters. Because with the trust with which they treat the ICO, they need more time to raise funds. I personally to extension am normally. For me it's just fun... well, not gonna pay, God bless him, goes to the other bounty.