Especially because each custom picutre icon would have to be reviewed, and it would take a lot of people to get through everyone. Considered as well, you would have to find people mature enough for the task, and almost nobody would be willing to do it for free. Let's say there's 10 people, and there's 50 people who make custom picture icons per hour. You pay all 10 people $15 an hour, and that's already $150. In consideration there would be people changing their icons to custom picture ones all around the clock. Let's say that month had 30 days in it. That would add up to around $10,800.