Grammar

Anonymous Should it be:Why would someone put...orWhy someone would put...

Why would someone put his finger in a beehive? (A question)
Why someone would put his finger in a beehive is beyond me. (A statement)

Both are possible.

Why would someone put crayons in the fridge? (question)
Why someone would put crayons in the fridge I'll never know. (statement)

Both can be correct, depending on the kind of question:

Why would someone put that there? (a direct question)
Why someone would put that there is beyond me. (an indirect question)

BillJ

If it's a direct question, then it's "Why would someone put (sugar on their chips)?"

However, this is also possible:

"Why someone would put sugar on their chips is a mystery, isn't it?"