Sorry to hear of your experiences.
I live in a mountainous area and there are a number of clubs and organizations, formal and informal.
There's three main categories that they tend to fall into:
1) Experienced / Casual
Target: experienced / higher level hikers (e.g. trail runners, those training for ultras, or are comfortable doing multiple summits in a day, etc.), who are usually quite familiar with the hikes in the area, and can tackle them at a faster pace
Intention: Have some buddies for your trip / group training
Style: Usually someone announces that they are going on a certain hike at a certain time, and those interested can join them there - a very casual approach to things. Basically, meet at the trailhead at X time and let's go. Due to the lack of structure, typically fast pace, and that they may be visiting more technical trails, not recommended for someone who doesn't fit the target profile.
2) Mixed / Affinity Organization
Target: any skill/comfort level
Intention: To bring people from a certain area or school together as a social activity
Style: There is a formal club that participants have to join, sign a waiver for, and pay dues, which are often assessed on an annual basis, but sometimes available on a per-trip basis as well. There is an organizer who does call-outs for events and they are often an experienced hiker with first aid training.
If someone is interested in a certain hike, they can reach out to the organizer to suggest it.
When calling out for an event, they will provide details (location, if vehicle needed, time, difficulty level, recent trip reports, equipment/supplies/money for gas, parking or campsite etc. needed, and if the club itself may have any equipment for rent), and ask potential participants to confirm if they are driving or available to drive, and if so, number of seats available, or if they need a ride.
The organizer will cap the size at whatever they are comfortable with (usually 20 or 30), and provide updates when it is full, or if more drivers are needed.
There are some standard rules (e.g. Trips are usually Saturday or Sunday, meet at X Community Centre at 7:45-8:00 AM for sign in and for distribution of maps and to go over back-up plans in case the parking is full, emergencies, etc., drivers depart at 8:15 AM sharp, and everyone meets up again at the destination parking together, though if group size is large enough, the organizer may allow splitting into two or maybe three groups based on speed)
2a) Mixed / Self Organizing
This is basically a variant of #2, where the group/club leader is more of a facilitator rather than an organizer. Members join, and their dues/donation, sign the waiver, but call-outs can be done by any member on the basis that they become the organizer for that hike, and on the expectation that they are familiar with that hike. The member would endeavor to ensure if possible that at least one person with first aid is on the trip, and following the trip, they would provide a trip report to the facilitator.
The facilitator may organize one or two general meetings per year.
It sounds like the event you joined is similar to that of #1, and perhaps going forward you may find a #2 or #2a type club/organization to be more suitable.
