Rust on brake discs. OK to ignore?

[Domo]

I'm going to assume all bikes (and most likely cars) suffer with this? Rust on brake discs. Besides squeezing a dry cloth through each hole after washing or getting caught out in a rain shower, I suppose it's OK to ignore? Just looks untidy. Thoughts?

Bike's kept in a garage. Around 450 miles on the clock.

 

[Domo]

Thanks for the tip. Doesn't bug me - caught my eye and wanted to make sure it won't lead to anything else like the wheels falling off!
No harm asking - and thanks for the reply.

@Acme. I'd at least keep all the plastic bits