This may seem like a dumb question...
Globe of Invulnerability has an area of a "10-ft.-radius spherical emanation, centered on you", but what if a gargantuan creature cast the spell?
Meaning it goes out an additional 10' beyond the creature, regardless of size? The problem is that's not what the spell says . I think yours would be the "common sense" answer, but it's not what's stated within the spell.