I suggest you explore the question with more granularity. Some people use Bitcoins for "criminal" transactions because they feel that particular laws are unjust, invasive, abusive or otherwise inappropriate.

You may find a difference in the percentage of people who are opposed to the use of Bitcoins to facilitate theft vs the percentage who are opposed to the use of Bitcoins to allow expats to send remittances to their family in countries the US government does not permit trade with, or the use of Bitcoins to avoid legal prohibitions of online gambling.