If there is one thing that Hatter likes about Alice's world other than Alice, it is the clothes.
Shops and shops filled with scads of clothes of every hue and texture. These are things that are hard to come by in good quality and in large supply in Wonderland. Hatter has a distinct memory of having to make use of his right fist on at least one occasion involving a particularly choice top hat. Acquiring large amounts of clothing, let alone nice clothing, is a battle where he comes from.
Here, they just call it shopping, and anyone can do it so long as they have a little plastic card, a few slips of printed paper, or a quick hand.
He doesn't advertise this addiction to Alice, because while she is well-groomed and certainly stylish in her own way, she doesn't have Hatter's lust for true variety in clothing, and she is suspicious enough of the fact that lately he's taken to changing his clothes at least twice a day. She doesn't seem to mind all the outfits, and Hatter doesn't make any serious fashion faux pas (although he is extremely experimental occasionally, with mixed results), so its not as if he is embarrassing to be around in public. She is even indulgent enough to go shopping with him, and if there is anything in Alice's world other than Alice and the clothes that Hatter likes, it is getting Alice to try on clothes.
There is a possibility that second to Alice herself, getting Alice to try on clothes is actually his favorite thing about her world.
"Hatter, I really don't think these things are supposed to go together." Alice complains, her shoulders drooping. Hatter is perched on a plush, round chair outside her dressing room, which she has just stepped out of. When she turns for him dubiously, the fabric of her combined outfits clings to her in just the right way, and Hatter grins.
"I don't really see a problem," he says, and Alice eyes him suspiciously.
"You said that about the last outfit, and even the saleslady thought that one was a bad idea."
Hatter leans back, resting his weight on the heels of his hands behind him, and tilts his head to one side to get a better view of her legs. "That outfit had its merits. I promise."
The last outfit had shown a delicious amount of cleavage in the front, and the skirt had been obscenely short in the back. In his opinion, it was an outfit she should wear every day, no matter the weather. In fact, the colder the weather, the better: in that last outfit, she couldn't wear one of those beastly contraptions she calls a bra. He had gone cross-eyed when she stepped out of the dressing room with that one.
When she huffs dispiritedly, he leaps to his feet in one graceful bound and takes her elbows in his hands, leaning in close. "Alice, my darling, my shimmering oyster of joy and delight --- " he pauses for dramatic effect, just to watch her fighting a smile as she looks up at him, "You are neglecting to see the point of this exercise."
Her dark eyebrows shoot up towards her forehead. "You mean, the point isn't finding me something nice to wear?"
Hatter leans back, his hands still cupping her elbows, and peers around the edges of Alice's dressing room door. The saleslady is nowhere in sight.
Quick as a flash, he twirls Alice back into the dressing room and locks the door behind them.
Whatever else Alice was going to say is swallowed by the toe-curling kiss Hatter plants on her sweetly protesting mouth, and it isn't long before he has her moaning and gasping up against the mirror on the dressing room wall. He plunges his hands into the dark, shining mass of her hair, relishing the weight of the feather-soft feel of it, before his fingers worm their way downwards. He is greedy for the feel of her skin, and when his fingers slip beneath the stretching fabric of her blouse to cup one warm, silken breast and she gasps into his mouth, he goes just a little bit mad.
His pants are down around his ankles and Alice is clinging to him like a burr and dissolving into a writhing pile of willing woman when a pounding on the dressing room door startles them back to reality. They freeze and stare at each other, both still caught up in a thick cloud of lust, their hearts pounding against each other's chests, and a voice calls through the door. "You're not allowed to share a dressing room!"
Hatter nearly drops Alice at this. He leans into her shoulder, laughing, and even though what was turning into a delightful afternoon shag has been rudely interrupted, he is incredibly cheerful as he pulls up his pants and helps a very flustered Alice back into her own clothes.
The saleslady is wearing a very disapproving frown when Hatter opens the door, and although Alice is blushing and ducking her head down in embarrassment, the flush of arousal still staining her chest and throat, Hatter is sporting a supremely smug grin.
As they walk away from the dressing rooms and towards the front of the store, Alice groans into the side of his arm, "We're never going to be let back in here again."
Hatter links his fingers with hers and looks at her out of the corner of his eye. On a whim, he sneaks a quick kiss on her cheek and says, "Alice, one of the things I like best about your world, is that there is always another clothing store."
She is silent for a moment as they exit the store, and it is only when they have gone around a corner and are no longer in view of the shopkeeper that Alice says, "Hatter, you still haven't told me what the point is to me trying on all these outfits. We never actually buy any of them."