[Petrochemicals (OP)]

I have a few scars on my hands, left hand mainly, ol' lefty is always suffering at righty's stupidity. I have scars from doing things on the knuckles mainly but in a few other places too. I know for a fact that the pads on my finger tips have had injuries, burns compression blisters and cuts but they miraculously heal without scars. Why is this?

[Kryptid]

It probably comes about as the effect of evolution on a vitally-important, highly-used body part. Your fingertips can expect to suffer damage/degradation throughout your entire life. As such, I would expect selection pressures to compensate by making fingertips good at healing.

[Colin2B]

It probably comes about as the effect of evolution on a vitally-important, highly-used body part. Your fingertips can expect to suffer damage/degradation throughout your entire life. As such, I would expect selection pressures to compensate by making fingertips good at healing.

That’s probably true. The outcome is that the fingertips are very well supplied with fine blood vessels and as far as I can tell a good blood supply is essential to good healing. Interestingly, if someone loses a slice of tip above the nail there is a good chance it will grow back - don’t try this at home kids!

[CliffordK]

One would note that hand palms, and foot soles have what is called "thick skin" which is different from the rest of your skin.

However, I agree with @Kryptid that there is a strong evolutionary advantage of tough skin on the palms and soles, and rapidly healing.  Note that animals such as cats and dogs also have "pads" on their feet which are quite tough, but they'll occasionally get it cut and it will heal.

[vhfpmr]

if someone loses a slice of tip above the nail there is a good chance it will grow back

It did.
In fact I can't even see or remember which finger it was now, after all these years.

[CliffordK]

if someone loses a slice of tip above the nail there is a good chance it will grow back

It did.
In fact I can't even see or remember which finger it was now, after all these years.

I've had a little damage to the tips of a couple of nail beds over the years. 

One, I touched the tip of the finger with a bandsaw about 30 years ago. 

It did heal, but I think I ended up with a little scar tissue under the nail, and it has never been quite perfect.  A slightly weaker nail, or a good place to get slivers or pieces of grass under the nail.