In OOTB stylesheets, we can see some examples of 'display:none' being used to hide field captions. For example, if we use a 'simple list' format and have PegaKM in our stack, the following styling applies:

.flex.content-simple_list>.flex.content-item>.field-caption {
    text-align: left;
    display: none;
    padding-right: 0px;
    padding-bottom: 0px;
    flex: none
}

In this case, providing a label in the section would have most people expecting the label to show. This is probably done less and less with more recent designs, but nevertheless, see the example below: 

Maybe this is something to take into account, or there can be a very good reason why a design like this is implemented OOTB :)