Competition between the maid cafes is fierce, but you really don't see that on the surface. When you walk down Chuu-ou Dori from the JR Akihabara station, there'll be 10 or 15 maids on either side of the street, often standing close by each other, trying to hand out fliers to their cafes. Generally, the pedestrians ignore them as they shuffle by, heads bowed down, staring at their shoes. Few of the maids succeed at getting anyone to take the fliers, and if they do, there's little interest in actually going to the cafes. If one person does choose to hit a cafe, that's one place with one more customer, while the other places go empty. So, the competition's not on the street. It's in the cafes themselves. And the fierceness surfaces in the ways each place decides to hold events.
The big holidays are pretty obvious. Most cafes will have a Christmas special, with the maids wearing red stocking caps and maybe red dress uniforms, and Halloween with its accompanying cosplay. The lesser known, more traditional Japanese holidays also have their own place on the maid calendars. Specifically, I'm talking about Hina Matsuri, March 3, with its display of little dolls on a tiered platform (the "hina"; "matsuri" means "festival"). When I visited Idol Produce Cafe on Mar. 2 (to be reviewed later), I noticed on the placemat calendar that there was going to be a Hina Matsuri event the next day. Wanting to know what that would entail, I dropped by again on my way to work.
In the case of IPC, the event was a little too low-key. One idol wore a traditional kimono while the others were in the standard school outfits. The menu listed the Hina set - a bag of sugar candy and a one-cup bottle of sweet sake for 1000 yen ($11 USD). While I was there for the next hour, nothing much happened. On the other hand, this time, there were two really well-dressed female customers at one table, one of whom was a regular. The other 6 people were young men, either job seekers, or college kids.
I was told that the idols would be singing on stage at 8 PM, but again, that was after my starting work time of 7:30. I did decide to get a dessert - sweet pancakes with drawings in chocolate syrup and a small scoop of ice cream. When the one idol arrived with the plate, all the others started squealing "kawaii" ("how cute") over the drawings. The pancakes were pretty standard, so nothing special there. 850 yen + the 500 yen cover.
Bottom line: most cafes will compete by offering different events throughout the year, and especially during the holidays. But, not all of the events will be that interesting. Moral: pick a cafe that you like, frequent it as you like, and wait until they have an event that you really want to see. Otherwise, going to a cafe at random could end up being disappointing (regardless of how fierce the competition is for your money). Or, don't go on a night when you have to work when the event takes place.