Actually a meetup I attended last Friday held in a spacious hall, and
it showed several coins' pros and cons with a BTC trend analysis.
In some conference, they only announced their strengths in this
field and their common message was 'I can provide right ICOs, so
you only transfer your
BTC to me right now'.
The difference I think, are
1. the attitude of hosts
2. the expectation of participants
If hosts use a meetup, then they like a specific discussion than
a general round table forum with experts, and participants also
expect more intimate situation than a formal one.
And conference would be ... you can guess.