It would be reasonable to expect that the job of these city officials should be to (a) encourage the people to visit parks even more; and (b) maintain the parks adequately to their usage - if people use the parks more then it obviously costs more to maintain, but it also obviously means that people are getting more benefit from the parks and they want them to be maintained more.
Enforcing the rules about littering and trampling flowers is part of maintaining the park; but if people are routinely staying past park hours (the whole concept of park hours is a bit strange to me, I'd expect parks to simply be unserviced but otherwise available 24/7), then likely that's a sign that these hours should be extended - the purpose of littering restrictions is obvious but the only legitimate purpose of restricted hours is that the population wants the hours to be restricted for safety reasons or whatever; if now it turns out that the population doesn't want that restriction anymore, then it shouldn't exist.