When I go away, with time to plan and pack, I always think ahead and pack accordingly. So in this case, if I was one of your volunteers I’d already be packing myself the following as standard:
- earplugs for room-sharing
- eye mask (probably no curtains)
- spf / aftersun / mosquito spray
- work boots
- lightweight summer robe or kaftan for over PJ’s
- comfy sliders
- small first aid kit
- san pro
Id just assume any group of practically-minded adults would pack the same - and might be a bit baffled at the over-display of you having also bought this anticipating that they wouldn’t have thought of packing such luxuries.
So I’d say try not to overthink it on the “little luxuries” side. Let the adults bring their own anticipated comforts (earplugs, paracetamol etc). Remember that you’re not running a boutique hotel and trying to preempt all of their personal comfort demands.
Youre there to keep the heavy cogs turning: a conveyor belt of big dishes of grub to be wolfed by the troops. A fridge full of beers, local plonk, bottles of water, pop.
Everyone gets given a towel and assigned a bunk / bed
You’re in charge of the lighting of and campfires or stoves, the nightly coordination of the laundry to your neighbour.
That’s it. Easy & simple. Military operation. It’ll be a huge laugh. And so rewarding
_All sat round the fire each night, exhausted, showered, belly full of delicious starchy Spanish stodgy, cold beer in hand.
Try not to add too many ‘extras’. Irrationally, I think I’d possibly feel a bit irritated by that if I was one of the helpers.