Really cool that you built this from scratch for so many major cities! I am located in Chicago but browsed SF and the list returned there looked like a logical categorization of events & things to do.
Re: your question of whether to pursue the project, my thoughts from the perspective of someone who works in the tourism & travel industry.
Collecting and aggregating event listings is, as you note, time consuming. It can't all be done by crawl/scrape. Curation is an important factor here, and so perhaps you tailor the product to the perceived needs of a specific type of end user.
First user type that comes to mind: those of us who maintained Facebook accounts for the event listings/invites, but have all but fallen off of Facebook over the years due to... everything else that's wrong with the product :)
I'll say this, too — Airovic is entering a space where your number one competition is Google. Google orients its event listings geographically, around a "place," and I think your opportunity is to orient around people and their preferences.
To that end, another competitor here is Spotify for concerts — much as I hate to admit this, as a retired "Cool Person," I'm generally made aware of bands I want to see touring in my area first by Spotify, and then by social and local media.
That said, in identifying and meeting the needs of a narrower band of users, you may find that emphasizing curation and personalization could position your product as a more useful method of discovery.