Your images are 3168 x 4752. (period).
The 72 is PPI (pixels per inch) and it's only there to tell the computer how big it should look on a monitor. You could change that 72 to 300 or 5000...it won't matter.
Your camera (like most DSLR cameras) shoots in a 2:3 ratio. This is perfect for 4x6 prints, 8x12 prints etc. But it's not the same ratio (shape) as a 5x7 print, an 8x10 print etc. So you do need to crop when you want those print sizes. You do loose some pixels, but don't worry about it. (unless you are cropping out a whole lot of the image)
Once you are aware of this, and have some practice, you can visualize an 8x10 crop when you are shooting and then leave yourself some extra space in the composition.
Other options, would be to just use 2:3 print sizes like 8x12 etc. or to print your images with some space around them. If you want to use a standard size frame, but keep the 2:3 ratio, you could cut (have cut) a custom size matte.