One reason they may be picking them back up may be because all the study articles for the month are in one issue. If they only got a few extras then it would be difficult to have enough every week. There are some jws that lose or forget theirs every meeting. My wife has brought the wrong magazines a few times, I just get any magazine and look like l am a zealous jw. I discovered that it doesn't make much difference If you have the right magazine anyway, it all sounds the same.
Some of jws make a big deal out of everything, and others could care less, just depends on which congregation you are in.