You might find [this meta.stackexchange post interesting](http://meta.stackexchange.com/questions/164080/why-can-only-moderators-protect-questions-less-than-1-day-old).

As someone who is on a site which also gets a lot of questions up there (some of which are of varying quality...) I absolutely error on the side of protecting them as protection against spammy types of answers.

Just a note - high rep users can only protect questions after a few days have passed. Moderators can protect immediately.