well I'm no chemist but I do love physics, particularly quantum physics...

so what if the Higgs actually exists but maybe it's not actually 'mass' as they claim it to be... i mean, they are calling it a 'characteristic', like 'charge' or something... so maybe it's a force, or a charge, or something like that which makes the small alteration in the higgs field. that's why it has no volume. unless the reason why there is a small alteration in the higgs field depends on the medium (or are we talking about a vacuum?). I mean if it's for sure that something is happening, there's gotta be a reason for it, so it should be either an acting force, or energy, or some sort of fusion... obviously more info needs to be given to get a better picture, but it's a start.