to find this highly irritating

[loonies]

When people use 'We' instead of 'you'/'they'/'him'/her'/individuals actual name. It seems to be done particularly when referring to young children or old people. Examples include 'Oh we're not the keen on eating our vegetables are we?' or 'Oh we do enjoy going for walks in the rain don't we'. Irritating and patronising!

I think your first example is a more sympathetic version of saying the same thing. To use 'you' with a child in that scenario is a little pointed. The second example...erm, maybe they do mean 'we'?

Being a bit sensitive over this aren't we?

The examples weren't great I shall have to try and come up with some better ones.

We agree, hobgoblin. It deflects some of the criticism if it is something like not eating veg, and to let a child know that they're on their own in enjoying walking in the rain would be mean and unnecessary.