Unless they have extended their exercise window beyond that standard 90d, those lottery tickets may cost a lot is money to retain after leaving for another job. So much so that companies exist solely to extend loans for them.
You don't get to just collect multiple lottery tickets without either going out of pocket or watering down your share significantly.
The thing is, most support agents only get a few shares.
Both of the last two companies I worked for, it cost me about $1,500 to exercise the shares I'd vested after about 2 years, and their 409a FMV was about $26k at the time I exercised them.
One of those companies has since gone public and my piddly little $1,500 became worth over half a million dollars.
It's absolutely a lottery, but if you get in places at the right times, I think it's worth collecting tickets rather than doing the same work for similar pay where you don't get tickets.
You don't get to just collect multiple lottery tickets without either going out of pocket or watering down your share significantly.