Why does nobody want to give Voldemort their wand?

You raised some good arguments in your comment. And if Voldemort's followers were smart enough, brave enough and selfless enough, they might've had more weight. But these aren't exactly traits shared by Death Eaters who mostly descended from the house of Slytherin. They run on self-interest, cold calculation, mistrust and fear. So they stall, torn between conflicting instincts of self preservation: Obey their powerful master to avoid further harm, or be rendered utterly defenseless. From the book:

The faces around him displayed nothing but shock; he might have announced that he wanted to borrow one of their arms.

The fact that even Bellatrix hesitates shows how valuable wands are to wizards; in fact, we see in Hallows how wands pretty much represent the magic in them when the Ministry strips them off Muggle-born wizards that it considers too 'human'. But it also shows us that some of Voldemort's once loyal servants are now miserable and stick around strictly out of trepidation, like the Malfoys... And Voldemort is asking them to hand over the last thing that might still protect them.

Wands are extremely personal items for a wizard, almost as much a part of themselves as any real body part. Without it they are defenseless. Giving up their wand would be like declawing a cat, leaving it defenseless.

Besides, no one at that table trusts Voldy. No one is there out of loyalty, but fear. As Voldemort says to them, not one of them tracks him down after his death at the Potters' hands, no one but Peter Pettigrew.

And Voldy is the type of person that would use you one second and kill you the next.

Anyone voluntarily giving their only line of defense up to a mad man is just as mad as him. Even though Voldy is stronger, each knew that without a wand they go from a handicap to fish in a barrel. With a wand they may have a chance, sans wand it would be a slaughter.

As Slytherins, they all tend to have their own self interests at heart. Each knew it would be best for them to stay quiet until their hands were forced. No need to give up until their bluff is called. A calculated risk based on group actions. There are n wands and Voldy only needs one right?

No one did because a wizard rarely would want to part with his or her wand.

Almost all magic is done with the use of a supporting tool or focus, typically a wand. On the subject of magic without the use of a wand, Rowling says:

You can do unfocused and uncontrolled magic without a wand (for instance when Harry blows up Aunt Marge) but to do really good spells, yes, you need a wand.

A wizard or witch is only at their best when using their own wand. When Harry's wand was broken, probably as a result of Hermione's ricocheting Blasting Curse. Harry and Hermione took turns using her wand, until Ronald Weasley returned to them carrying wands he had taken from Snatchers. Thereafter, Harry made do with a blackthorn wand, although it did not work as well for him as his own wand had.

Every single wand is unique and will depend for its character on the particular tree and magical creature from which it derives its materials. Moreover, each wand, from the moment it finds its ideal owner, will begin to learn from and teach its human partner.

Wikia01 / Wikia02 / Wikia03 / Wikipedia

They all might know about how you must kill the owner to make the wand truly work, as shown when Voldemort kills Snape for the elder wand without a care. I would assume he might as easily kill me to make the wand more powerful if I were to give him it. Plus there's the whole thing about being defenseless, and being close enough with your wand that it would be like cutting off an arm. The last two mentioned earlier.

They are unwilling to give their wands to him for the same reason you would be unwilling to put down the Swiss knife (say) when confronted with a tiger!

Although it (wand or Swiss knife) is quite ineffective against the danger facing you, you would still feel better with some sort of protection against him.