Non-cat visitors enjoying ferals leftovers?

Throwing out the casting net for some opinions and advice yet again.

Quick synopsis: We have a 20+hour a day patio feral (about 20 months old?) and the occasional visiting 3+ maybe 4+ year old feral (once every 3 days on average, doesn't stay around after eating usually though).  Possible problem is that we apparently also have a nightly visitor adolescent opossum (year or younger) who snarfs the leftover food or licks the plate/has some water.  There is also a once a week (to my knowledge) raccoon visitor (good size so presumably few years old), and very rare (once a month maybe) adult opossum (big guy! didn't know they got that big).

My question is the level of concern I should have for the younger male feral.  He hasn't seem to 'get into it' with them yet.  I have seen him just sit on the patio furniture and watch the baby possum wander in and feed.  Even watched him just sit there and watch the raccoon once.

I figure I will just start pulling in the plate and bowl post-feeding and see if they stop coming around but IF that doesn't work...any suggestions on keeping the unwanted feral riff raff without chasing away the accepted feral cats

Dumdum (younger feral) appreciates any advice   (not meant to be disparaging name but after losing previous ferals to unknown circumstances we didn't want to name him originally and just kind of coined him on his habit of immediately leaving cover of the patio and going into the garden when it started to pour...heh)

Taking the food up at night is always a good idea. The two feral boys will learn quickly when the dinner hour is over. Raccoons can be dangerous to ferals. They can be carriers of rabies. Possums can get testy, too, so I wouldn't take any chances.

We have the same problem with raccoons. I've started feeding the stray a little earlier in the evening hoping that he will eat, then retreat. Also, remove any birdseed or sunflower seeds because raccoons love those too. I've stopped composting because they went through that nightly. Once I saw our stray stand his ground against a fox. I've noticed that if he's full, he will just sit and watch any other animal that comes in to the yard. It's only when everyone is hungry that things get testy.

Definitely bring the food inside at night.  During the cold winter months I can occasionally leave some dry food out for my boys, but they learn really quickly that they need to eat early as the food disappears.  Mine eat 2x a day so they are always waiting for me by 6:30am each day!