I have one cat who is in love with plastic bags. If you bring a bag home and set it down, Mr Grey immediately will climb in! He doesn't even care if you pick the bag up with him in it (I did that once or twice hoping it would discourage him). I always empty all bags right away and throw them away or put them in a drawer so he can't reach them.
Today someone took a pack of paper towel rolls out of the package they come in (plastic wrapping/bag) and put it on the floor for a minute... I looked down and there was Mr. Grey with his head and front feet inside!

I took him out and reminded them not to ever leave any plastic bags out!
I also try make sure that no bags or totes with handles/loops are left out, especially paper bags... My family members would bring some groceries in one of those paper bags with the twisted rope-looking handles and once one of the cats climbed inside and then tried to climb out by sticking his head through a handle and got twisted up in it so I had to extricate him. Not safe! So now I either throw them out right away or I cut the handles off.
I have two of those cat tubes, but they don't like those half as much as a paper bag.