iPads for kids here too… I love the control and visibility I have over their accounts…I can control what apps go on there, screen time, parental controls etc. share content…its just like one ecosystem where the device is just a way to access it. As stand alone devices I’m not sure there are any benefits to Apple over other equivalent (and often equivalently priced) alternatives, but the ecosystem when you’ve got several devices especially across the family, seems particularly slick with Apple. Could be the case that Android might have caught up…don’t know but for our family to switch over to Android it would be a significant investment and alot of faff for probably zero benefit.
But yes, no need to buy direct from Apple. I got ours from Argos. There are no downsides for not buying from Apple…you can still purchase extended warranty from Apple should you wish to. I also got my iPhone X from Argos, it developed a problem and I was reluctant to get Apple involved as I’d dropped the phone a few months before so thought they’d not touch it with a barge pole, but I booked a tech appointment via the website, they sent a box through for me to return it to them and a few days later it was returned fixed for zero charge no questions asked – they couldn’t give a toss I’d not bought it direct from them or that it was damaged. Couldn’t have been easier.