Yes, I pay for games.
Wish I had a way of seeing all of my purchases in one list... if anyone knows of a way to do it, let me hear it, thanks!
I don't like the "free 2 play"... or as Satoru Iwata said "free 2 start" model, because it's far too easy (purposely) to loose sight of how much you spend on a given game. So I simply don't pay for anything in-game.
I very rarely pay for stuff that's completely clear and one time only, like "removing ads".
So if it's a game that requires you to pay to continue playing or something like that (games that cripples the gameplay unless you pay), I simply don't play and drop the app. There's plenty more out there to replace them, and they are mostly past time.
Now, honestly, I download lots of game to test them. And I don't play that much with my WP phone, first because I hate touchscreen controls, second because I only play games on it when there's no other choice, which doesn't happen a lot for me.
But for the past end year holidays (when I travel and get away from my gaming devices) I remember paying at least for two games which I played to the end, and must account for the longest times I've spend gaming with my Lumia 1020: Puzzle Quest 2 and Nightmares from the Deep, from Artifex Mundi (thanks WPCentral for recommending those!).
Oh, I just searched my mail and found all bills. I also bought: Temple Run OZ, Heroes of Kalevala, Let's Golf 2 and tons of non gaming apps.
So I must've paid for about 10 apps and games over the course of 2 to 3 months... also worth noting that I had a problem with the store early on right after I got my phone because some brazilian banks wouldn't accept credit card purchases in it, something related to exchange rates or something.
Also: I have an iPad 2 and have always used the same system for game purchases: no in-game spending unless it's for one time only and very clear purpose. I always like to quote a game as the ideal model for free 2 play games: Beastie Bay from japanese developer Kairosoft.
It's an incredibly complex and complete game in which you can pay 2 remove ads (that are not even intrusive in the first place... it's banners that lays outside the game screen), and than way later on in the game you can pay to create some pets or monsters, but it's in no way necessary... you probably got them anyways by playing the game regularly. I paid for the ad removal because I liked the game very much and wanted to support the devs.
Anyways, that's my take on it.