Then you'd use the monolith on the Lava Golem... *facepalm* when you get it
Oldtrees i see your point but look on this side
A tower creates 1, ONLY 1 extra quanta - for speed. What good is 8 extra quanta when playing 8 towers? A lot.
BUT!
An upped monolith creates +1|+0 for as long as a creature is alive.
equation where x=amount of towers played and y= number of turns since play:
Towers:
(x+x*y)
Pillars:
(x*y)
Monolith
(x*y) but it's got a bonus attack power, which would be (x*y)
Towers give a measly extra x, which is pretty much darn useless, unless you get an awesome combo of the perfect amount of towers/creatures. I mean, if x=5 and y=4, after 4 turns (since y=4), towers will create 25, whereas monoliths create 20+20 DAMAGE. That is equivalently more than a tower creates quanta. Increase y, and you'll see that monolith gets boosted twice with the y.
Is 20 damage worth more than 5 quanta? That is the question... 
That is indeed the question but I believe Ash Eater answers it nicely. 2 damage per turn for 1quanta +1card. Unless the draw cost is greater than the quanta cost then 1atk=<1quanta.
Also the extra x quanta occurs on turn 1 meaning -1 TTW compared to pillars. Hence the benefit of a monolith must be able to compete with that initial turn loss and the resource loss.
Also just for added emphasis: X=4, Y=5 (assuming a free Ash Eater pet for the pure monolith entry to make sense)
4 Towers + Ash Eater Pet
24

+10 damage (1 target)
2 Towers + 2 Brimestone Eater + Ash Eater Pet
20

+ 30 damage (3 targets.)
4 Upped Monoliths + Ash Eater Pet
20

+ 30 damage (1-4 targets. 1 in this example)