A Question For The Lowball Commem People...

Not likely.
Most people who love coins grit their teeth when the possibility of deliberate damage to them arises.
If the most common grade for a particular issue is MS63, then so be it. In this case, you won't make it more valuable by wearing it down to a rarer grade.

If cost is not in question, what would you prefer:
A 'common' Spanish Trail in MS63, or a 'rare' Spanish Trail in F12?

It all depends on outlook. Some, like our lowball collectors here, would rather have the F12 (if not lower). It would also be preferred that the coin honestly circulated to its worn state.

I'm about to start on a lowball 7070 because it's less cost-prohibitive than one with really nice coins. I think worn coins have a lot of character: They had a long tough life in circulation and deserve to be set aside. No two circulated coins are exactly the same, while a blast-white MS65 may not even look all that different from a 5x more expensive MS67.

Now I wouldn't take an old rare commemorative to wear down. At least, not an uncirculated one. Maybe a circulated coin, especially with problems. I have modern pocket pieces to wear them down; it's interesting to see how they wear.

Agreed.