Creepers spawn even in very bright areas, e.g house

Dear Sir and Madam,

the problem is that I see especially creepers spawning in bright areas where they shouldn't spawn actually.
They often destroyed my house when there was just a creeper in a hidden corner of my house
But I also think that the creepers (or maybe the mobs in general?) spawn a way too much in Minecraft.
I have set the difficulty to "Hard", anyway the creepers shouldn't spawn in these bright areas.

I would thank you very much if a developer could take of this not by letting mobs spawn in such bright areas (e.g below lamps in the house)!
By the way in my house there is enough light and there are no gaps which could cause mobs to come inside.
I have experienced this issue now for a lot of times.

Best regards,
Janek P.