Favorite implementation has to be KSBD Mammon's Vault. Before you can actually get to the money, you have to go through an entire dungeon's worth of mimics. Rugs? Mimic. Random scattered coins? 90% mimic. An entire grand foyer the size of a dwarf hold filled with chairs? MIMICS except for one!

And then.... the door to a new world was opened for the mimic.

well the whole chest thing dates back to video games trying to adapt DND to a visual media, TTPG loot is more logical. As for mimics again from DnD in which they can actually be everything. including a piece of armor because your DM is a sadist and you just signed up for a 1v1 death match.

Nothing like having a random chest in the dungeon filled with normal supplies like blankets or cleaning tools. When players find those are usually like "I'm not sure if I'm disapointed by the chest or for expecting something else..."

Also fun fact: there is a carnivorous plant who feeds on a small mammal but instead of trapping and killing it the plant provides sugar in exchange of pee and poop that fertilizes it.

The bugs predate on the crab explaining why sometimes adventurers find a chest full of treasure bugs, it used to be a chest with a mimic crab but the bugs ate it.

In Dungeon Meshi the dungeon used to be a city explaining why there are treasures in it. There are two types of mimics, one are bugs disguised as coins/jewelry that swarm people. The other are large hermit crabs who hide in anh type of container (chests, wardrobes, helmets) depending on their size.

I have seen enough hentai to know where this is going.

Frieren : "This looks like a perfectly normal chest and I have to open it !"

What people think of for a Mimic is the large chest you'd have Link pulling an item/weapon from after beating a boss.
The more common mimics are Tables, Doors, Beds, Out Houses, Ladders leading to a wooden ceiling with a trap door, A Bar, Barrels of Mead.

Who can resist modern plumbing?

Mimic disguised as a door lures out some lightly armored guy to stick wires into its holes. More insidious would be to disguise as a treasure. Disguised as a painting or tapestry would be interesting.

I too would appreciate more sensible implementation of treasure chests. Like, put medication, antidotes and other items of similar nature in logically placed medicine cabinets and infirmaries, food in kitchens and refrigerators, weapons and ammo in armories, and so on.

What is this, Made in Abyss?

An alternative view is that the treasures are there to lure the adventurer to go deeper in search of even better loot just to get killed in some trap or by monsters where their corpse fuels the dungeon and the loot and their OWN gear gets redistributed throughout the dungeon.

reminded me of other comic where the mimic mimicked a waifu prisioner in torn clothes

But the spell that detects mimics is only 99% accurate! The real discoveries are made by people who look for that 1%!