Why are major league baseball fields not standard in size?

[JustinD]

As I remember, the teams were building these oversized parks to attract top pitchers that thought it would help their stats. The opposite was true with smaller parks and power hitters.

While it does seems the smaller parks have attracted some hitters more so than parks with a huge porch. The pitcher attraction of a big park seems to have been more overshadowed with location and money.

I think it's a questionable practice as I have a hard time comparing home run stats from Fenway vs Comerica Park (Coors field is a whole different bag of worms).

I would be ok with uniformity but I can't see it ever happening. What I would like to see is a minimum size for some of these, even if it costs some seating.