Are those Bio-Ethanol heaters any use?

ToneControl

I was wondering if one on top of a tiled outdoor dining table might keep people around the table warm on a chilly evening

Kittyfrisk

If they mention feeling chilly, berate them for being a proper bunch of softy Walters.
They'll then either shut up or their sense of self righteous indignant outrage will warm them through for free  

Funkfingers

ToneControl said:

I was wondering if one on top of a tiled outdoor dining table might keep people around the table warm on a chilly evening

Only until one of your guests necks the alcohol.