They might prefer just keeping it to themselves to avoid the ridicule and the endless questions.
These people, you will never hear about in the news or on the internet. They will never tell their experiences publicly.
1. The poster is sensible, provides information (and no, that info does not have to identify them or their precise location!), and listens to opinions.
2. The poster doesn't consider their sighting as some sort of unquestionable truth, or definitive evidence for ET, or the 'Best ever..', and then get all upset when the viewers don't seem to share their enthusiasm..
So yes, people's 'sightings' are sometimes attacked vigorously, but let's face it, it depends on the nature of the sighting and the forum - and a lot of the flack happens when they respond badly to criticism. I've seen many examples of sightings that have been sensibly discussed/debated, where the poster happily engaged with us 'evil debunkers' and accepted the questioning and investigation in the knowledge that it was a quest for truth/explanation, rather than an attack on their 'baby'.. In several cases I have assisted behind the scenes to do some deeper analysis to help - if they are willing to back up their sighting, so am I willing to help, even though the explanations are almost always prosaic - you never know when a decent one might appear..
Yes, there are many anecdotes out there.
(and.. that's largely because there are many things up in the sky and as observers, we are all pretty crappy at it (myself included), yet easily impressed)
So .. No, the plural of anecdote is not data (let alone evidence, or proof, or wisdom..)
I agree that:
If the person posts the imagery and runs for it, or doesn't engage properly in any discussions, or is posting someone else's imagery where the same applies... it's just another anecdote, worth exactly what I paid for it.