Too right Kaz, I'm afraid I've had to take a few things back to Morrisons - a big nuisance when it's in the next town
As for the weevils, nope, not safe - they don't crawl in, they arrive and hatch out in the bag (I think that's right), and then spread into any other flour nearby. In this case my chief suspect is a bag of Lidl's bread flour, which was the most recently opened bag. I've been buying it for ages, I think it's just bad luck. The flour's all on the top shelf of the larder unit.
I do keep virtually everything in containers, but because of bread-making, I have white and w/meal bread flour, plain and self-raising, all open - and have been looking for suitable containers for a while. I really want ones I can put the bag into, rather than empty it in - flour makes such a mess!
They've all fitted into the freezer bags so hopefully that will do for now.