It's kind of a shitty policy. On the one hand I get keeping the wages down and knowing that you'll have applicants for those jobs when people leave.On the other side it's one of the reasons a lot of people only stick around for a year or two. Good workers find better jobs, and there are plenty of noobs who couldn't spork a takeoff halfway rideable to save their lives.
It's frustrating when I go places and want to take a few park laps and it's very clear that the park crew doesn't give a fuck, are complete idiots, or both.
Also OP. It's a decent gig to do for a bit if you're interested. Honestly if you can shovel or rake with complaining all the time, and have some concept of what park features should look like, you're probably off to a better start than a good percent of day crew guys.