[AblemTee]

Having never played a match play event, that thought never occurred to me. That said, I often see the pro's take the putt even after it's been conceded. Or retaking a missed putt and losing the hole.

Not exactly sure what you're saying here. Once a putt is conceded in a match, the player can pick up or play it out, but his score for the hole remains the same. A conceded stroke cannot be declined, nor can it be rescinded. Once the concession is made the hole is over the player receiving the concession.

I don't know what you mean by a player retaking a missed putt and losing a hole. I think what you're seeing is a player losing the hole by missing the putt (or possibly having the next putt after the miss conceded for a halve), then just trying it again for practice. Practice is allowed by the rules on or around the green just played or on the next tee box unless it is prohibited as a condition of the competition.