I don't know many kids who didn't snoop to try to find out what they were getting, and plead guilty to being one of them. That being said, I never ever found them - my mother was a master at hiding them. The other thing was that she never gave us reason to suspect that she was "hiding something". Kids like the challenge of finding something hidden - "hide and seek"?? We never saw her go into the attic to hide the gifts or down into the basement. THere were occasions that she'd go into the attic or down in the backroom to the basement, but would always come out with something that she "needed". If she heard us snooping around (sometimes kids don't realize just how well sound travels), she'd tell us to quit "messing around back there" giving the excuse that either stuff was organized and she didn't want us messing it up or somehow getting hurt, that there wasn't anything "back there" that we needed to be into anyway. Kind of took the fun out of snooping around somewhat.
My grump with my husband is that his parents who live in Idaho shipped gifts to us already - he let our 5 year old open the box, and then placed the presents under the tree. I told him....BEGGED him not to do that, but he is one of those "always right" types and said "that's what they always did growing up." We NEVER did that growing up. There were no presents under the tree until Santa came. Just as I told him would happen, our 5 year old has begged to open the presents every day since. She doesn't understand that Christmas is still 16 days away and thinks that just because there's snow outside then it's time for Santa to arrive. He finally admits I was right, but at what cost? But I digress...
Anyway...my suggestion: Don't make a big deal about it and don't even mention it. Give him the presents anyway. I would go ahead and wrap them and find a different place to hide them (like the trunk of the car? or put them in a storage box on a shelf in the garage?). If he mentions them, say, "What are you talking about? Show me what you're talking about...." and he goes to show you and they aren't there, you can say, "Hmmmm...Are you sure they were here? I wonder what happened to them....well we'll just have to wait until Christmas to find out what happened." Anything he can think of to explain what happened will be worse than anything you tell him anyway. Then when he gets the gifts at Christmas, maybe he'll be relieved that he got what he thought he was getting.
For what it's worth....and good luck!!