Alfraks
I'd like to also add some stuff to this if I may.
Namely how to, and how not to pull off micro transactions:
How to do it:
Elite, Dangerous.
Elite dangerous uses microtransactions to fund further development of new "content". It works via a season pass system, each year new content will be released and people who want access to it. For instance, at launch the game was £20, and the first season pass was Horizons, it over the course of a year, added planetary landings and revealed the Thargoid aliens (in fact I styled the Anhysbys around their ships, but theirs are not living ships).
Alongside this of course, the horizons pass allowed access to engineers so you could using gathered resources upgrade a ship further, as well as adding Anti-Thargoid weapons for sale at planetary installations.
Is all that worth £20 extra? Hell yes it is, admittedly the content is quite a grind to unlock... but that is more the base games fault.
More microtransactions exist in Elite, but they are ALL cosmetic, you simply cannot buy in game ships or money via real cash.
Games that got it wrong (and make loads more money)
Grand theft auto V
GTAV is a good game, and its singleplayer on PC with mods is great... but Gta Online... that is where the microtransactions kick in. Via making everything in game expensive, and giving players no access to good money making methods without them first owning an expensive facility, Rockstar and Take two practically force people to either hack, or purchase in game money via shark cards. The real issue is that shark cards cost up to £60! That is more than the entire game's price! And when someone calculated how much all the vehicles in a dlc cost, it came to 50 million in game money... for around £60 you get 8 million in game money... yeah.
Star Citizen
Yes, a game that isn't even out yet, but still has microtransactions of its own... well to call them micro is a huge understatement, you can fund the games development by preordering not yet made ships, that doesn't sound too bad, until you realise that the ships cost THOUSANDS of pounds/dollars/euros... and recently they added a new preorder pack, only viewable to people who already paid more than 1000 real money on the game, it costs 27k
A game that Kinda did it ok
Rainbow Six Siege
R6S works off another season pass content system, but one issue I have with it, is that although you can get everything via playing the game, it takes so long people are forced to pay up unless they want to play loads and loads, although its microtransactions can be so low cost to buy them it is less bad compared to GTA for example.
