Well, maybe some do now. But my son and I are cleaning his room this morning, and getting his twin mattress out of the way was enough work that I’m catching my breath to ask the collective geniuses here - why was it such a pain? I seem to recall moving larger mattresses, when moving, without handles too.
IME, most do; some don’t. A lot of the time, I’ll find on older mattresses that they’ve broken off over the years, but you can clearly see the eyelets where they were attached. It seems to me that the smaller mattresses are more likely not to have them.
They do, it’s just that they are of next to no use. As a mind greater than mine once said, “It’s not the weight, it’s the awkwardity!”
You can move a mattress a number of ways, none of which is helped any by the handles.
I’m an expert mover, having done it dozens of times for myself and friends. Fridge? No problem. Washing machine? No problem? Even a freakin’ PIANO… No problem.
I’ve always heard you aren’t supposed to lift the mattress by those handles. Tip #15 from here, a site on mattress care agrees with me.
This site on mattress care agrees, also.